Bilingualism as a first language: language dominance and crosslinguistic influence

Abstract

Even though research on bilingual first language acquisition (2L1) could be conceptualized as monolingual acquisition (L1) of two individual languages, the fact that in 2L1 acquisition there is exposure to input from two languages has consequences in terms of how the two language systems interact in the mind of the bilingual. This century has seen two important developments in this respect. First, a consensus seems to have been reached on the idea that the two systems are differentiated from the early stages (e.g. Genesee 1989; De Houwer 1990; Genesee, Nicoladis & Paradis 1995; Koppe & Meisel 1995; Genesee 2003). The second development is related to how the 2L1 language faculty compares to the L1 language faculty and the consideration that the grammatical processes and operations in both bilingual and monolingual speech must be accounted for in the same terms (MacSwan 2000; Liceras, Spradlin & Fernandez Fuertes 2005; Liceras et al. 2008, among others). However, while it is unquestionable that L1 and 2L1 acquisition share similar mechanisms and processes, there are core issues such as language dominance, crosslinguistic influence and code-mixing that are specific to simultaneous bilingual acquisition.

Full text

Language Acquisition and Contact in the Iberian Peninsula
Alejandro Cuza and Pedro Guijarro-Fuentes (eds.)
Bilingualism as a first language: language dominance and crosslinguistic influence
Raquel Fernández Fuertes (Universidad de Valladolid) and Juana M. Liceras (University of Ottawa)
ABSTRACT
Even though research on bilingual first language acquisition (2L1) could be conceptualized as monolingual
acquisition (L1) of two individual languages, the fact that in 2L1 acquisition there is exposure to input from two
languages has consequences in terms of how the two language systems interact in the mind of the bilingual. This
century has seen two important developments in this respect. First, a consensus seems to have been reached on
the idea that the two systems are differentiated from the early stages (e.g. Genesee, 1989; De Houwer, 1990;
Genesee, Nicoladis & Paradis, 1995; Köppe & Meisel, 1995; Genesee, 2003). The second development is related
to how the 2L1 language faculty compares to the L1 language faculty and the consideration that the grammatical
processes and operations in both bilingual and monolingual speech must be accounted for in the same terms
(MacSwan, 2000; Liceras, Spradlin & Fernández Fuertes, 2005; Liceras et al., 2008, among others). However,
while it is unquestionable that L1 and 2L1 acquisition share similar mechanisms and processes, there are core
issues such as language dominance, crosslinguistic influence and code-mixing that are specific to simultaneous
bilingual acquisition.
In this chapter, we address these three language contact phenomena by analyzing spontaneous and
experimental data from the simultaneous bilingual acquisition of English and Spanish by two identical twins in
Spain (FerFuLice corpus in CHILDES) as it compares to data from other 2L1 and L2 children and adults. We
conceptualize language dominance in terms of the computational value of grammatical features in a given
language. And so, the dominant language is the one that provides the functional category whenever that category
is highly grammaticized. Crosslinguistic influence between the two languages of a bilingual is analyzed in the
case of sentential subjects and copula predicates and we propose that the occurrence as well as the directionality
of influence is linked to lexical specialization. Therefore, the presence of two sets of subjects (i.e. overt and null)
and two sets of copulas (i.e. ser and estar) in Spanish leads to a lack of negative influence from English into
Spanish. However, a facilitation effect appears in bilingual English as seen in bilinguals’ lower copula omission
rates and lower null subject rate. In terms of code-mixing patterns between Determiners and Nouns, child and
adult spontaneous production data differ from experimental data in that while the former show a preference for
the Spanish Determiner (the category which is more grammaticized), the latter prefer the English Determiner.
We propose constructs such as the Grammatical Features Spell-Out hypothesis or the Analogical
Criterion to account for these patterns. The analysis of these language contact phenomena provides an insight on
how language properties shape bilingual production.
1. INTRODUCTION
While the mechanisms and processes that shape bilingual first language acquisition (2L1) should, in
principle, resemble those of monolingual acquisition (L1) in the case of each of the languages involved,
the fact that in 2L1 acquisition there is exposure to input from two languages forces us to confront two
fundamental research questions: whether and how the two language systems interact in the mind of the
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bilingual and what the outcomes of this interaction may be. Consequently, the main objective of this
chapter is to discuss specific ways in which these research questions have been approached in the
acquisition literature.
The very title of the chapter makes it clear that we will be dealing with simultaneous bilingual
acquisition, namely with children who are exposed to the two languages from birth, rather than so-
called sequential (or consecutive) bilingual acquisition which deals with children who are exposed to
the second language after being exposed to the first language for at least two or three years (Baker,
2011; De Houwer, 2009; Silva-Corvalán, 2014, among others). When the acquisition of a second
language occurs past three years of age, it is usually referred to as child second language acquisition
(cL2) rather than sequential bilingual acquisition (Meisel, 2008).
Some of the most salient outcomes of 2L1 acquisition are language dominance, crosslinguistic
influence, and language mixing. Language dominance has been defined in terms of relative proficiency
(Grosjean, 1982, among others) or relative speed of development (Wapole, 2000) and it has been
measured in relation to language production and to language processing. While there is not a unified
definition of language dominance in young bilinguals, an inventory of linguistic diagnostics along with
other types of diagnostics, has been proposed to identify the dominant language. A first objective of
this chapter is to propose a definition of language dominance that is not necessarily equated to
proficiency but to the grammaticalization of features in the various languages.
As for crosslinguistic influence (i.e. Döpke, 2000; Genesee, Nicoladis, & Paradis 1995; Liceras,
Fernández Fuertes, & Alba de la Fuente, 2012; Müller, 1998; Nicoladis, 2002; Yip & Matthews, 2000),
it is important to point out that, within the view of the bilingual mind that we maintain, and even if the
two language systems share a single computational component, the realization of universal principles is
to be mediated by the existence of two lexicons and two phonological components. This implies that
the combinations of features present in the functional categories (i.e. pronouns, determiners, auxiliaries,
complementizers …) and the lexical or substantive categories (i.e. nouns, lexical verbs, adjectives …)
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in the two languages may differ and, therefore, may result in crosslinguistic influence. It may also be
the case that a feature or a set of features be realized as one lexical item in one language but as two
lexical items in the other language. A case in point is the values of copula be in English that are realized
as two different lexical items —ser and estar— in Spanish. The obligatory use of overt subjects in
English but not in Spanish and the systematic availability of null subjects in Spanish but not in English
have also been discussed as relevant loci for crosslinguistic influence. Thus, a second objective of this
chapter is not only to discuss some potential loci for crosslinguistic influence in 2L1 acquisition but
also to show that, while crosslinguistic influence can cause interference, it can also have a facilitating
effect.
Finally, code-mixing or code-switching has also been investigated as an outcome of 2L1
acquisition, both as a diagnostic for language dominance as well as a reflection of how the properties of
the two language systems may interact. We will use code-mixing and code-switching interchangeably
even though the first term has been used to refer to mixing that occurs before children have
incorporated the functional categories of the two languages (Köppe & Meisel, 1995).
In order to discuss the above-mentioned outcomes, we will use data from the simultaneous
bilingual acquisition of English and Spanish in Spain. We will specifically discuss 2L1 data from the
bilingual twins in the FerFuLice corpus in CHILDES (MacWhinney, 2000; Fernández Fuertes &
Liceras, 2010) in relation to L1 monolingual acquisition of both Spanish and English and paying
special attention to copula omission and null and overt subject production, two constructions that have
received a great deal of attention in the 2L1 acquisition literature (i.e. Paradis & Navarro, 2003; Silva-
Corvalán, 2014). This will contribute to the understanding of individual bilingualism which can then be
used as a point of comparison with societal bilingualism (Bathia & Ritchie, 2012).1 In our specific case,
we will be discussing a case of individual rather than societal bilingualism and a situation where
1 The type of contact that has been mainly studied is the one in which the language that may eventually become non-
dominant, and here we are using the term as the equivalent of proficiency (e.g. Spanish as minority / heritage language in
the US), may have a facilitating effect in the acquisition of the dominant language (e.g. English as majority language in the
US).
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Spanish is the majority language while English is the minority language. Nonetheless, we want to
address language dominance, crosslinguistic influence and code-mixing as outcomes of bilingualism
that can be investigated across the board, as determined by the mere contact between two different
language systems and, in principle, abstracting from the specific setting as such or the specific amount
of input.
2. THE CHARACTERIZATION OF BILINGUAL FIRST LANGUAGE ACQUISITION
As Baker (2011), referring to Grosjean (1995, 2008) and Jesnner (2008), points out, two
contrasting views of individual bilinguals have been argued for in the literature: the view of the
bilingual as “two monolinguals in one person” (the “fractional” view) and the view of the bilingual as
having a unique linguistic profile which is not the sum of two monolinguals (the “holistic” view).
While the conceptualization of the problem is different because it pertains only to the initial stages of
acquisition, the availability of two language systems is also at the core of the debate between those who
argue that the mind of the young bilingual child contains a single language system (Lindholm &
Padilla, 1978; Redlinger & Park, 1980; Vihman, 1985; Volterra & Taeschner, 1978) and those who
defend that the two language systems are differentiated from the early stages (De Houwer, 1990;
Genesee, 1989, 2003; Genesee et al., 1995; Köppe & Meisel, 1995). This debate seems to have been
won by the latter. However, we would like to frame the fractional/holistic debate as well as the
single/two different language system view within the Minimalist framework, as argued by MacSwan
(2000, 2014), where the grammatical processes and operations in both bilingual and monolingual
speech must be accounted for by the same universal mechanisms. This is so because the bilingual
language faculty is made up of two lexicons and two phonological components but a single language-
specific computational system: the only one available for human language.2 That is, under Minimalist
2 Even though the two lexicons proposal is intrinsic to MacSwan’s model, a distributed morphology account can dispense
with the two lexicons requirement, as was timidly suggested in Liceras, Fernández Fuertes, Perales, Pérez-Tattam, and
Spradlin (2008, footnote 8).
4

premises, this view of the bilingual language faculty offers a universal framework within which feature
activation will proceed depending on the specific language, as well as feature valuation and the
outcomes of the operations MOVE, MERGE, and AGREE. Therefore, this view provides us with the
framework needed to discuss the outcomes that are specific to 2L1 acquisition but are, at the same
time, shaped by the mechanisms and processes that pertain to L1 acquisition. It also implies that
Universal Grammar is a central component of the Language Acquisition Device (LAD) and that
linguistic structures reflect mentally represented knowledge (Meisel, 2011, among others).
Even though in terms of ability, the field of bilingualism differentiates between active and
passive bilinguals, we will only be discussing the acquisition of two languages that leads to active
(comprehension and production) bilingualism. It is a fact that ability is a dimension of a continuum
(Valdés Kroff et al., 2011) and that in the course of development the bilinguals whose data we will be
discussing might become passive bilinguals in one of the two languages, but discussing this potential
developing outcome is out of the scope of this chapter.
Active bilingualism may not necessarily imply that the receptive and productive competence in
the two languages is “balanced” and this is why language dominance has been systematically discussed
in the bilingual literature in general and in the 2L1 acquisition literature in particular.
Petersen (1988) lists prevalence of overall functional words from one of the two languages as a
diagnostic internal to the linguistic system and parents’ perception and amount of exposure as
diagnostics external to the linguistic system. Nicoladis and Secco (1998) define language dominance in
terms of relative vocabulary size in each of the two languages while for Genesee et al. (1995) or for Yip
and Matthews (2006) the dominant language is the one for which the child has a higher Mean Length
of Utterance (MLU).
We agree with Baker (2011) that balance and dominance tests are dependent upon language
proficiency and performance and can only partially access the bilingual’s language capacity and
language ability. Also, dominance need not coincide with balance and, as Baker (2011) puts it, “it is
5

possible to be approximately equally proficient in two languages, yet one may be dominant” and so, for
instance, “speed of processing may provide evidence about balance but not about dominance in actual
language use” (p. 35). In fact, language dominance can change overtime and it may be easier to identify
at the lexical and phonological levels than at the morphosyntactic level, a difference that has been
systematically pointed out in the case of language transfer.
As for transfer, while it may not be possible to differentiate transfer from crosslinguistic
influence, some researchers (i.e. Silva-Corvalán, 2003, 2014) argue that they are different because the
effect of crosslinguistic or interlinguistic influence is quantitative rather than qualitative. For instance,
the presence of more overt subjects in the Spanish of English-Spanish bilinguals (Silva-Corvalán,
2014) than in monolingual Spanish, or the lower omission of copula be in the English of English-
Spanish bilinguals (Fernández Fuertes & Liceras, 2010; Liceras et al., 2012) would be identified as an
instance of crosslinguistic influence. However, the use of an expression such as dame una mano in
Spanish for “give me a hand” would be an instance of transfer since the Spanish expression is échame
una mano (“throw me a hand”). We adopt this distinction and follow a quantitative approach to
crosslinguistic influence in subsequent sections.
Crosslinguistic influence has been said to be pervasive at the interfaces between internal and
external modules of language, such as the syntax-pragmatics interface (i.e. Tsimpli & Sorace, 2006).
However, many researchers have challenged this view of the so-called Interface Hypothesis both as a
locus for crosslinguistic influence or for learning difficulty (for an overview of the Interface Hypothesis
see Sorace (2011) and commentaries). We should also point out that there are not many studies that use
data from the early stages of 2L1 acquisition to test whether crosslinguistic influence plays a relevant
role at the interfaces. As we have indicated above, we will discuss crosslinguistic influence as having a
facilitating or an interfering effect in 2L1 development and will argue, as in the case of language
dominance, that the features and combinations of features that make up the functional and lexical
categories of the language pair constitute a valuable tool for both predicting and accounting not only
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for the type of influence (facilitating or interfering) but also for its directionality (i.e. which language
will be the source or locus of influence and which one the target of influence).
Language dominance is directly related to whether the outcome of bilingualism consists of a
balanced or an unbalanced bilingual. However, this outcome cannot be taken as categorical but rather
as a continuum when it comes to comparing individuals. Overall, input and social factors seem to play
an important role in the degree of proficiency as measured by monolingual standards achieved by any
given bilingual in the minority language (the one that does not have an official status in the country). In
the case of the two English-Spanish bilingual brothers whose recordings were analyzed by Silva-
Corvalán (2014), at the age of six, the older brother had achieved a higher degree of proficiency than
his younger sibling in some specific Spanish structures, a situation that according to this author is to be
explained as a result of the greater amount of Spanish input received by the older sibling. Nonetheless,
Silva-Corvalán (2014) argues that when compared to monolinguals, these bilinguals’ English was not
negatively affected by Spanish. On the contrary, the rich morphology of Spanish had a facilitating
effect in that the bilinguals acquired the obligatory subject requirement and the English verb
morphology earlier than their monolingual counterparts. Thus, crosslinguistic influence is one of the
specific outcomes of 2L1 acquisition that we will discuss in this chapter.
3. THE FERFULICE CORPUS: SIMULTANEOUS ACQUISITION OF ENGLISH-SPANISH
BY TWO IDENTICAL TWINS
In order to discuss language dominance and crosslinguistic influence, we use spontaneous and
experimental data from the simultaneous bilingual acquisition of English and Spanish by two identical
twins who were born and grew up in Spain and we compare these data with available data from other
bilinguals and monolinguals.
The twins, Simon and Leo, were born in Salamanca (Spain) from an English-speaking mother
from the US and a Spanish-speaking father from Spain. The parents have always used the so-called rule
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of Grammont, the one parent-one language strategy, and so the father always speaks to the children in
Spanish and the mother always addresses them in English. According to an extensive and a
comprehensive parental questionnaire, this practice was followed from the moment the twins were
born. The parents generally speak Spanish with each other, except during the summer when they travel
to the United States for approximately two months or when a monolingual English speaker is present.
Therefore, this is a case of bilingual English/Spanish first language acquisition in a monolingual-
Spanish social context, a type of bilingualism which is referred to in the literature as individual
bilingualism (Bhatia & Ritchie, 2004).
The spontaneous data from Simon and Leo come from the FerFuLice corpus available through
the CHILDES project (MacWhinney, 2000). The data cover the age range of 1;01 to 6;11. A total of
178 sessions were recorded on videotape and DVD, of which 117 were in an English context (i.e., with
an English interlocutor such as the interviewer or their mother) and 61 in a Spanish context (i.e., with a
Spanish interlocutor such as the interviewer or their father). The Spanish recordings were made at
intervals of 2 to 3 weeks until age 3;00 (with some interruptions during the summer holidays), and then
once a month after that. The English recordings were sometimes made more frequently, but the sessions
were usually much shorter and recorded on consecutive days. The children were recorded in naturalistic
settings, usually at home, and appeared together in the majority of the sessions. They were mostly
engaged in normal play activities with the interlocutor.
As in Fernández Fuertes and Liceras (2010, Table 2), a comparison of the twins’ MLUs in both
languages with the corresponding MLUs of two age-matched Spanish monolinguals and two English
monolinguals yields very similar results3. As argued by Hickey (1991) and Miller and Chapman (1981),
3 The MLU (Mean Length of Utterance) is derived from two totals: the total number of utterances and the total number of
either morphemes (standard MLU) or words (MLUw) for each speaker and in each file/transcript. MLU calculations for the
twins were based on word measures (MLUw), while those of the English monolingual children were measured on
morphemes (standard MLU). When comparing standard MLU and MLUw values, Malakoff, Mayes, Schottenfeld, and
Howell (1999) found that MLU correlates with MLUw at .97 for English , and Aguado (1988) found a correlation of .99 for
Spanish (see MacWhinney, 2009, p. 103).
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among many others, MLU has consistently been found to be the most stable measure of comparison
between children.
Taking into account the information gathered both in a parental questionnaire and in an
extensive vocabulary check-list, as well as the corresponding MLUs with age-matched monolingual
English and monolingual Spanish children, Fernández Fuertes and Liceras (2010) conclude that the
twins’ proficiency in English and Spanish is quite balanced between the two languages and relatively
equal to their respective monolinguals in both languages.
The experimental data from the twins that we discuss in this chapter come from a code-mixing
acceptability judgment task that we describe below. We compare the twins’ data to data from other 2L1
bilingual children and adults.
4. LANGUAGE DOMINANCE IN BILINGUAL FIRST LANGUAGE ACQUISITION
The notional definition of language dominance that constituted the point of departure for more
theoretically grounded research refers to the situation where one of the languages of the bilingual is at a
more advanced stage and develops faster than the other, a definition that is, in principle, dependent on
measuring the proficiency in each of the languages of the bilingual. For Yip and Matthews (2006)
language dominance is a property of the bilingual mind which is assessed by comparing the MLU in
the child’s two languages. The language with the higher MLU is the dominant language. They argue
that the directionality of transfer goes from the language with higher MLU to the language with lower
MLU and that there is a correlation between the MLU difference and the pervasiveness of
crosslinguistic influence.4 These authors specifically show that in the English of English-Cantonese
bilinguals who are Cantonese-dominant, null objects —which are illicit in standard English— are used
4 Yip and Matthews (2006) use the term syntactic transfer to refer to the type of influence that takes place between the two
languages of bilinguals, an influence, they argue, that takes place at the level of competence (p. 101).
9

more frequently by those with a larger MLU differential use than by those with a lower MLU
differential use.
According to Petersen’s (1988) version of the dominant language hypothesis, in an English-
Danish bilingual system where the dominant language is Danish, (1) but not (2) may be a code-mixed
utterance, whereas, the opposite would be true if English were the dominant language.
(1) Hendes dolly
[her dolly]
(2) Her duke
[her dolly]
Thus, the dominant language provides the functional category of the switched NP —Danish in (1) and
English in (2).
Liceras, Spradlin, and Fernández Fuertes (2005) and Liceras, Fernández Fuertes, Perales, Pérez-
Tattam, and Spradlin (2008) propose a reinterpretation of the concept of language dominance using the
theoretical framework provided by the Minimalist Program (Chomsky, 1995, 1998, 1999), and in the
spirit of MacSwan (2000). They formulate the Grammatical Features Spell-Out Hypothesis (GFSH)
according to which, in the process of activating the features of the two grammars, the child makes
choices in terms of the language that will provide the functional vocabulary to a given functional-
lexical mixing. These choices are dependent on how these features are ‘grammaticized’ in the two
grammars, namely their degree of ‘saliency’ and their ‘computational value’. This implies that in the
case of English-Spanish child acquisition data, mixed utterances such as (3) will prevail over (4)
because the Spanish Determiner but not the English Determiner carries a Gender feature.
(3) El(masc.) book
[the book]
(4) The libro(masc.)
[the book]
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Evidence for the GFSH is provided by data produced by Mario (Fantini, 1985), Manuela
(Deuchar & Quay, 2000), Simon and Leo (Liceras et al., 2008), and five children studied by Lindholm
and Padilla (1978). In the data from these nine English-Spanish bilingual children, instances of
utterances such as the ones in (3) account for almost all cases of mixed Determiner+Noun utterances,
as depicted in Table 1, adapted from Liceras et al. (2008).
TABLE 1. Child bilingual D-N mixings: Spanish/English, French/English and Italian/German
Manuela
[Deuchar
CHILDES]
Mario
[Fantini,
1985]
Leo
[Fernánd.
et al.,
2002-2005]
Simon
[Fernánd.
et al.,
2002-2005]
5 children
[Lindholm
& Padilla,
1978]
Michael
[Swain,
1972]
Lisa
[Taeschner,
1983]
Giulia
[Taeschner,
1983]
Language
pair
Sp / Eng Sp / Eng Sp / Eng Sp / Eng Sp / Eng Fre / Eng It / Ger It / Ger
Def Art
‘the’
1 — 18 — 1 — 3 — 7 2 1 — 10 4 5 6
Ind Art
‘a/n’
4 — 16 — 3 — 1 — 5 1 2 — 1 6 1 8
Dem.
‘this’
— 2 2 — — — — — 6 — — — 1 — 8 1
Indef.
‘another’
11 — 1 — 17 — — — — — — — — 5 — —
Poss.
‘my’
— — 6 — 1 — 1 — — — 3 2 1 1 3 2
Total 16 / 2 43 / — 22 / — 5 / — 18 / 3 6 / 2 13 / 16 17 / 17
Child bilinguals systematically choose the Spanish Determiner because they have to specify the
features that will make the computational component of the Spanish system work, and this
computational component happens to require this type of AGREE operation. In fact, it follows from the
GFSH that the free morphemes which encode highly grammaticized features are especially important
for the requirements of the computational system and, therefore, for L1 acquisition. This preference for
the Determiner which is marked for gender also shows in the case of the French-English bilingual
(Swain, 1972) in Table 1 (column 7) since, although there are only eight DPs (Determiner Phrases) in
total, six have a French Determiner and only two, an English Determiner. The GFSH also predicts that
in a language pair where gender is equally grammaticized in both Determiners, no preference for either
Determiner will appear because the bilingual will have to activate both features in the two languages.
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As Table 1 shows (columns 8 and 9), the code-mixed utterances produced by Lisa and Giulia
(Taeschner, 1983) support this prediction.
According to Ong and Zhang (2010), the GFSH is also supported by the fact that their English-
Mandarin bilinguals overwhelmingly prefer the use of Chinese Determiner + English Noun switches.
What these authors argue is that, due to the fact that Mandarin Nouns do not inflect for number, the
reported preference is triggered by the lexical category, the English Noun, rather than the functional
category. This is so because the English Noun has the added feature [Number]. So as per the GFSH, the
preference goes in favor of the language whose features are more relevant for the computational
component, which in this case happens to be the English Noun, thus making the Chinese Determiner +
English Noun switches the favored option.
Further evidence for the GFSH comes from the DPs produced by the English-German
bilinguals in Jorschick, Endesfelder Quick, Glässer, Lieven and Tomasello (2011), since, regardless of
the dominance, these children use significantly more mixed DPs with German Determiners and English
Nouns than English Determiners which German Nouns, which is expected, given the fact that German
Determiners but not English Determiners bear the Gender feature.
In summary, and even though more analyses of naturalistic and experimental data are needed,
what the bilingual mixed DPs evidence is that language dominance can be defined in relation to how
children activate the formal features of language, which in turn determines how features are
represented in the mind of the bilingual.
5. CROSSLINGUISTIC INFLUENCE IN BILINGUAL FIRST LANGUAGE ACQUISITION
Even if the two languages are differentiated from the early stages of acquisition, as stated in the
Language Differentiation Hypothesis, 2L1 research has been concerned with how the simultaneous
development of the two L1s of the bilingual proceeds. In particular, bilinguals’ two L1s have been said
to develop either autonomously, and, therefore, in a similar way to their monolingual counterparts; or
12

interdependently, and so phenomena such as crosslinguistic influence appear, which make bilingual
development different from monolingual development. Some studies comparing bilinguals and
monolinguals have found no differences in their developmental paths (e.g. De Houwer, 1990;
Nicoladis, 1994; Paradis & Genesee, 1996) and this has been so in several areas of grammar: functional
elements such as verb finiteness, negation, and weak and strong pronominal subjects (Paradis &
Genesee, 1996), root infinitives (Unsworth, 2003), pronominal objects (Paradis, Crago & Genesee,
2005/2006), subjects and objects (Serratrice, 2002; Serratrice, Sorace & Paoli, 2004) and, in the case of
Spanish, null and overt subjects (Liceras et al., 2012; Liceras, Fernández Fuertes & Pérez Tattam,
2008).
Other studies have found differences between monolinguals and bilinguals attributed to
crosslinguistic influence, that is, to the transferring of properties from one L1 to the other L1.
Crosslinguistic influence has also been attested in different studies (e.g. Döpke, 2000; Fernández Fuertes
& Liceras, 2010; Hulk & Müller, 2000; Liceras & Fernández Fuertes, 2017; Liceras et al., 2012; Müller,
1998; Paradis & Navarro, 2003; Yip & Mathews, 2000) and in different grammatical areas (e.g.
phonological, morphological, and syntactic) as well as in different interfaces (e.g. the syntax-
pragmatics and the syntax-lexicon/syntax-semantics).
In summary, the characterization of crosslinguistic influence has been linked to linguistic theory,
language dominance or input and there are two factors that have centered most attention in this respect:
the effect of crosslinguistic influence (i.e. facilitating or interfering) and the directionality of
crosslinguistic influence.
5.1. The effect of crosslinguistic influence in 2L1 acquisition
When the properties of one of the L1s (language A) are transferred into the other L1 (language
B), in other words, when there is crosslinguistic influence, two possible outcomes appear: delay and
acceleration (Paradis & Genesee, 1996). This is seen in the attainment of the adult grammar properties
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as well as in the amount of non-adult-like cases that characterizes child grammars. If delay appears, the
influence from language A to language B leads bilinguals to acquire the properties of the adult B
grammar later and to produce a higher rate of non-adult-like constructions if compared to their
monolingual peers. Crosslinguistic influence, thus, has an interfering effect. If acceleration appears,
bilinguals acquire the adult grammar earlier than monolinguals and this would be so because some
grammatical properties are acquired earlier in some languages. Therefore, if a property is already
acquired in language A, it could be transferred to language B making bilinguals produce the adult
structures in language B sooner than would be the norm in monolinguals. Crosslinguistic influence, in
this case, has a facilitating effect.
In the case of the copula, it has been shown that Spanish children seldom omit the verb in these
constructions (Bel, 2001; Sera, 1992). However, Becker (2000) showed that English children go over
an initial omission stage in which they omit the copula as in (5).
(5) a. I _ (am) in the kitchen [Nina 2;01] (Suppes 1974, CHILDES)
b. Patsy _ (is) a girl [Peter 2;03] (L. Bloom 1970, CHILDES)
Becker (2000) argues that, while omission is higher in the case of predicates denoting temporal
properties (5a), it is significantly lower in copula predicates denoting permanent properties (5b). In the
case of Spanish-English bilinguals, Fernández Fuertes and Liceras (2010) found very low copula
omission rates both in the Spanish and in the English production of the children and for both predicate
types. The comparative results of these studies appear summarized in Table 2, adapted from Becker’s
(2004) Table 1 (p. 159) and from Fernández Fuertes and Liceras (2010).
Table 2. Explicit copula in Spanish-English bilinguals and monolinguals
Copula with
permanent
Copula with
temporal
14

properties properties
English monolinguals
(Becker, 2000)
% of explicit copula [EN] 76.3% 18.8%
Spanish monolinguals
(Bel, 2001)
% of explicit copula [SP] 99.5%
Spanish-English bilinguals
(Fernández Fuertes & Liceras, 2010)
% of explicit copula [EN] 91.2% 88.6%
% of explicit copula [SP] 96.7%
In particular, while no differences appear between monolingual and bilingual Spanish (Bel, 2001;
Gaulin, 2008) where percentages of overtness are above 95%, bilingual English is different from
monolingual English in this particular area of grammar. Given that the adult grammar (i.e. the use of
the copula) is acquired earlier in Spanish than in English, Fernández Fuertes and Liceras (2010) explain
the low rates of copula omission in the English of these bilinguals as a sign of positive crosslinguistic
influence from Spanish into English. That is, bilinguals transfer into English the properties they have
already acquired in Spanish and, as a result, less non-adult-like cases are produced and the adult
grammar is acquired earlier than in English monolinguals. This facilitating role of Spanish is triggered
by the presence of two copulas in Spanish (ser and estar) and the division of labor they have: ser
depicts individual-level predicates and estar stage-level predicates (as in Carlson, 1977; Schmitt &
Miller, 2007). As opposed to the saliency of Spanish in the use of the two copulas for the two predicate
types, in English, both types of predicates are depicted by copula be.
In the case of sentential subjects, children acquiring Spanish and English produce cases of
subject omission, as in (6), in spite of the fact that null subjects are possible in adult Spanish but not in
adult English.
(6) a (it) Roars [Simon 2;05] (FerFuLice corpus)
b. (yo) Tengo más [Manuela 1;11] (Deuchar corpus)
[(I) have more]
15

The patterns of subject production/omission have been the focus of attention when comparing
the monolingual and bilingual acquisition of Spanish and English. If crosslinguistic influence occurs
from English into Spanish, this could be reflected in the overproduction of subjects in Spanish; if it
goes from Spanish into English, the English of the bilinguals could contain more null subjects than
those characterizing the production of English monolinguals. Liceras et al. (2012) and Liceras and
Fernández Fuertes (2017) have carried out a comparative analysis of Spanish and English subjects by
analyzing the spontaneous production of monolinguals and bilinguals. The results appear in table 3.
Table 3. Sentential subjects in Spanish-English bilinguals and monolinguals
Child Spanish English
null pronoun null pronoun
Simon [EN/SP] 86.6% 13.4% 18.7% 81.3%
Leo [EN/SP] 85.8% 14.2% 20.1% 79.9%
María [SP] 90.9% 16.7% ---
Naomi [EN] --- 37.9% 62.1%
Table 3 shows that, in the Spanish spontaneous production, the rate of null versus overt
pronominal subjects produced by the bilingual children and the monolingual child reflects the
implementation of adult Spanish concerning sentential subjects: the preference for null subjects versus
pronominal ones. The pattern of the monolingual child (María) is very similar to that of the bilingual
children which points to the lack of crosslinguistic influence from English into Spanish in the
bilinguals’ Spanish production.
However, when comparing null and pronominal subjects in the English production of the three
children, data show that the monolingual child (Naomi) produces a significantly higher number of non-
adult null subjects than the bilinguals. Liceras and Fernández Fuertes (2017) attribute this lower
production of null subjects by the two bilinguals to Spanish playing a facilitating role. As in the case of
the copula, Spanish has two different realizations of the subject: null, licensed by a rich verbal
inflection, and overt. This makes bilingual children realize earlier than monolinguals that the null
16

subject is not an option for English verbs. Therefore, crosslinguistic influence from Spanish into
English makes bilinguals reach the adult grammar earlier than monolinguals.
Silva-Corvalán (2014) in her study on the spontaneous production of two Spanish-English
bilinguals finds different patterns from those in Liceras and Fernández Fuertes (2017). By analyzing
the data longitudinally (from age 1;06 to 5;11), she attested an increase of pragmatically inadequate
pronominal subjects in Spanish, which she attributed to crosslinguistic influence from English and, in
particular, from the English [subject pronoun + verb] string (pp. 163-4). This influence, which has an
interfering effect, is the reflection of Spanish being the non-dominant language as it is the language in
which the children receive less input. In the case of the copulas ser, estar and be, no influence from
Spanish into English or from English into Spanish is attested as the bilinguals behave similarly to the
monolinguals. In fact, the few errors in the children’s Spanish copula production are not omission
errors (as those reported by Liceras & Fernández Fuertes, 2017) but commission errors (e.g. uses of ser
in estar-contexts or the reverse) and are always produced by Brennan, the child who deviates from the
Spanish adult target more notably as he has had less exposure to Spanish (pp. 44-5 and 53). Silva-
Corvalán argues that crosslinguistic influence is determined by the dominant language and the two
siblings in her study were clearly English dominant. Our interpretation of these results when compared
to those of the two bilinguals in Liceras and Fernández Fuertes’ (2017) study is that there must be a
threshold, a minimum competence for crosslinguistic influence to take place and so, while the twins are
rather balanced, Brennan’s Spanish is quite weak and, therefore, does not trigger influence.
Paradis and Navarro (2003) investigate crosslinguistic influence from English into Spanish in
the subject production of a bilingual child exposed to Cuban Spanish. Given the fact that the use of
subject pronouns is more abundant in Caribbean Spanish than in other varieties of Spanish, Paradis and
Navarro (2003) cannot conclude whether it is this specific type of input or rather crosslinguistic
influence that accounts for Manuela’s larger production of overt subjects when compared to the
monolingual children. In fact, Liceras et al. (2008) and Liceras and Fernández Fuertes (2017) have
17

shown no indication of explicit subject overuse in the production of the two bilingual children they
analyze (table 3 above). Since these children were exposed to peninsular Spanish, it may well be the
case that Manuela’s overuse of overt subjects be a consequence of the type of input to which she was
exposed, rather than of influence from English.
5.2. The directionality of crosslinguistic influence in 2L1 acquisition
Crosslinguistic influence between the two L1s of the bilingual can go in the direction of
language A to language B or the reverse. As we have indicated above, while some researches relate the
directionality of crosslinguistic influence to dominance so that influence goes from the dominant to the
non-dominant language (e.g. Silva-Corvalán, 2014), other researchers argue that the nature of
grammatical properties can also dictate the directionality of crosslinguistic influence. Namely, if a
language presents a lexical-syntactic distinction that is absent in the other language (null and overt
subjects or ser and estar copulas in Spanish), this language may be a good candidate as the source of
influence (Liceras et al., 2012). This implies that in the case of Spanish-English bilinguals,
crosslinguistic influence will go from Spanish into English and not in the reverse direction, and this
would be so regardless of dominance. However, as we indicated above, we believe that for
crosslinguistic influence to occur, a certain degree of competence in Spanish, in this case, is necessary.
If the level of Spanish is too low, it would behave as an L2 and, in that case, influence will not take
place.
Hulk and Müller’s (2000) proposal also takes the linguistic specifications of each language as a
determinant factor when predicting directionality of influence. These authors propose that two
conditions are required for crosslinguistic influence to take place: (i) that the structure in question be
located at an interface and (ii) that the language which is influenced contain structures that children
may mis-analyze as mirroring those of the influencing language. Specifically, Hulk and Müller (2000)
propose that object omission occurs at a high rate in the French of child French-German bilinguals
18

because (i) omission in German is governed at the syntax-pragmatics interface and (ii) because French
clitic constructions could be analyzed as instances of object omission by the bilingual child, given that
the post-verbal position is empty because the object clitic pronoun is placed before the verb. The
conditions proposed by Hulk and Müller (2000) are put to the test by Liceras et al., (2012) as predictors
of the directionality of crosslinguistic influence between English and Spanish in the case of sentential
subjects and copula constructions. As for subjects, crosslinguistic influence from English into Spanish
leading to an overproduction of pronominal subjects in bilingual Spanish is not expected to occur since
(i) English pronominal subjects are a pure syntactic phenomenon and are, therefore, not located at an
interface; and (ii) as null subjects in Spanish are a robust phenomenon, children would not mis-analyze
the Spanish input in terms of the obligatory presence of English pronouns. In fact, as table 3 above
shows, no overproduction of pronominals occurs in the Spanish production of these bilinguals.
If crosslinguistic influence from Spanish into English takes place, it would result in the
overproduction of null subjects in English. If so, crosslinguistic influence would have an interfering
effect. However, this is not expected either since (i), although pronominal subjects in Spanish are
governed at the syntax-pragmatics interface, null subjects, i.e. the transferred property, are a pure
syntactic phenomenon; and (ii) it is far from clear that English would provide robust superficial input
which could be mis-analyzed as mirroring the Spanish structures where null subjects are licensed,
since, in English, null subjects with inflected verbs only occur with coordinated structures. As seen in
table 3 regarding the effect of crosslinguistic influence and as predicted under this view of
crosslinguistic directionality, no overproduction of null subjects in the English of these bilinguals
occurs.
6. CODE-MIXING
Code-mixing or code-switching has also been investigated as an outcome of 2L1 acquisition.
Zentella (1981, 2000) defines code-mixing as alternating languages in unchanged speech situations.
19

Cantone and Müller (2008, p. 811) consider code-mixing (CM) the ability of a bilingual speaker to use
both languages within a discourse (inter-sentential CM, as in 7), or within an utterance (intra-sentential
CM, as in 1 to 4 above), according to grammatical and socio-linguistic constraints.
(7) Sometimes I’ll start a sentence in Spanish y termino en español (Poplack, 1980)
[sometimes I’ll start a sentence in Spanish and I finish in Spanish]
CM constraints have been related to language dominance as discussed in section 3. Linguistic
constraints such as the equivalence constraint (Poplack, 1980), the functional head constraint (Belazi et
al., 1994) or the matrix language frame (Azuma, 1993; Myers-Scotton, 1995) share: the assumption
that CM is constrained by rules different from those of the languages intervening in the mixing, that is,
by a grammar of its own (the so-called third grammar); and the fact that they are too general in that, for
example, these constraints disallow mixes at boundaries where CM actually happens in the spontaneous
production of bilinguals.
MacSwan (1999, 2000), however, proposes that only the grammars of the two languages
involved constrain language mixing so that no additional constraints are required. MacSwan (2000, p.
45), taking the Minimalist Program (MP) as a framework, defines code-switching “as the simple
consequence of mixing two lexicons in the course of a derivation” which emphasizes the role of the
lexicon (and the features it encodes) when accounting for CM. The MP also guides the analysis carried
out by Liceras et al., (2005), Liceras et al. (2008) and Liceras, Fernández Fuertes, and Klassen (2016).
These authors carry out an analysis of Spanish-English CM in the spontaneous production of child and
adult 2L1 bilinguals as well as in the experimental data of child 2L1 bilinguals. They focus on the
specific CM Determiner + Noun, in (1), (2), (3), (4), and as in the examples in (8).
(8) a. los rockets [Mario 3;08] (Fantini, 1985)
20

[the rockets]
b. el cake [Manuela 2;02] (Deuchar, CHILDES)
[the cake]
c. la rock [Leo 3;05] (FerFuLice, CHILDES)
[the rock]
d. the vaca (Lindholm & Padilla, 1978)
[the cow]
e. the piscina [Simon 4;04] (FerFuLice, CHILDES)
[the swimming-pool]
These authors were concerned with the prevalence of one functional category over the other
(Spanish Determiner, as in 8a-8c, or English Determiner, as in 8d and 8e) and, in the case of the
Spanish Determiner, with gender agreement (the so-called analogical criterion where the Spanish
Determiner agrees with the English noun as if the English noun ‘inherits’ the gender features of the
Spanish translation equivalent noun). Under the analogical criterion (AC; a term initially proposed by
Otheguy & Lapidus, 2005), a contrast is established between the Spanish Determiner mixes in (9).
(9) a. elmasc. book=libro (masc.) [+AC]
[the book]
b. lafem. book=libro (masc.) [-AC]
[the book]
In (9a) the Spanish masculine Determiner agrees in gender with the English Noun as the
English Noun (book) bears the corresponding masculine feature of the Spanish translation equivalent
(libro). In contrast, in (9b) there is a mismatch of gender features between the feminine feature of the
Spanish Determiner and the masculine feature that the English Noun inherits from its Spanish
21

translation equivalent. This idea of imposing gender on the English Noun makes it possible that the
valuation of gender features in the CM phrase proceeds as in the Spanish monolingual DP.
What Liceras et al., (2005, 2008) show is that, regardless of dominance, as defined by Petersen
(1998), Spanish-English 2L1 bilinguals (both children and adults) have a very similar behavior in the
spontaneous production of mixed Determiner-Noun sequences. In fact, as shown in table 4, Spanish
Determiners are clearly favored in Determiner+Noun mixes by both children and adult 2L1 bilinguals,
and this is so regardless of whether they are rather balanced (as in the FerFuLice corpus) or whether
Spanish is their dominant language or not (as in the Deuchar corpus).
Table 4. Code-mixed Det-N sequences: the spontaneous production of 2L1 bilinguals
SP Det + EN N EN Det + SP N
Children Deuchar (CHILDES) 16 2
Fantini (1985) 4 -
FerFuLice (CHILDES) 7 -
Lindholm & Padilla (1978) 18 3
Adults Myers-Scotton & Jake (2001) 810 14
Jake, Myers-Scotton & Gross (2002) 161 0
Moyer (1993), Moro (2001, 2014) 213 2
To account for these preferences, Liceras et al. (2008) formulate the Grammatical Features
Spell-Out Hypothesis (section 3) and formalize the AC as the Gender Double-Feature Valuation
Mechanism in order to capture the strength of linguistic features and, in particular, of gender features
that leads to (i) the preference for the functional category which is more grammaticized (i.e. the
Spanish Determiner) as it encodes gender features; and (ii) the need to enforce gender agreement
between the Spanish Determiner and the English Noun as a linguistic operation rooted in the mind of
Spanish-English bilinguals.
This preference for the Spanish Determiner in production is not seen, however, in the case of
the experimental data these authors analyze. In their case, the experimental data are elicited via an
acceptability judgment task where participants have to rate a sentence containing CM between
22

Determiner and Noun as in (10) using a judgment scale with emoticon faces, as in (11). The 2L1
bilingual children tested range between the ages of 6 and 12 years and include the two children in the
FerFuLice corpus as well as a group of 2L1 bilingual children with a similar linguistic profile (i.e. they
also live in Spain and come from families where each of the parents is a native speaker of one of the
two languages and where the one parent-one language strategy of communication is used with the
children).
(10) a. El niño está en el plane Spanish Det, [+AC], MM
[the child is in themasc planeSpanish masc]
b. El señor está mirando por el window Spanish Det, [-AC], MF
[the man is looking through themasc windowSpanish fem]
c. The man is falling to the suelo English Det, Spanish masc N
[the man is falling to the floorSpanish masc]
(11)
Qué hace esta chica?
She is reading the revista.
The results of the judgment task (figure 1) show that the 2L1 children significantly prefer
sequences with an English Determiner (the two rightmost columns) over sequences with a Spanish
Determiner (remaining columns to the left) (p=.013). This is, in a way, to be expected as this CM
structure has less processing costs given that no gender valuation operation needs to be implemented as
the English Determiner carries no gender features.
23

0
1
1
2
2
3
3
4
4
Figure 1. Code-mixed Det-N sequences: the experimental judgments of 2L1 bilinguals
In the case of the Spanish Determiner CM structures, there is a preference for [+AC] options
that is almost statistically significant (p=.068). That is, this group of 2L1 bilingual children rate CM in
(10a) more favorably than that in (10b). This preference for the matching option seem to suggest that
Spanish gender features have a high representational value in the mind of these bilinguals in that in
they need to implement this valuation procedure between the gender features of the Spanish Determiner
and those of the Spanish translation equivalent of the English Noun.
Studies like Liceras et al. (2008, 2016) point to, at least, two issues that have often been
discussed in the analysis of CM in 2L1 bilingual acquisition research: the role of language dominance
and the social status of CM. With respect to dominance, and given the results presented above, the
Grammatical Features Spell-Out Hypothesis captures a view of dominance based on the features
encoded in the lexicon of a particular language and on the saliency these features have in this language.
Therefore, the dominant language would be the one whose features are most grammaticized because
they are the ones that would guide how structures are generated, regardless of whether this particular
language is the one in which the bilingual is most proficient or to which he has been more exposed.
The social status of CM has to do with whether CM is part of the speech of the community and,
therefore, a common practice, or rather a more ad hoc phenomenon. And this is linked to the social
context in which the 2L1 bilingual is immersed. As seen in section 1 above, there are different 2L1
acquisition contexts, so that, while some are more restricted to the family context (as in individual
24

bilingualism), others are part of a broader social context (as in societal bilingualism). Some authors
have suggested that the study of CM should be limited to those 2L1 bilinguals who actually use CM on
a daily basis, that is, to code-switchers (e.g. Guzzardo Tamargo, Valdés Kroff, & Dussias, 2016; Valdés
Kroff, Dussias, Gerfen, Perrotti, & Bajo, 2016).5 However, potentially all 2L1 bilinguals can code-
switch and have intuitions about code-switched structures.6 Besides, as shown in table 4, children who
are immersed in an individual bilingualism context (Spain in the case of the FerFuLice corpus, or the
UK in the case of the Deuchar corpus), also produce instances of CM. Furthermore, and in the case of
experimental data, what is being tested is the internal knowledge speakers have of their two grammars
and how these grammars interact. The fact that the judgments, as shown in figure 1, are around the mid
value 2 could be accounted for in this respect: these speakers are not used to code-switching. However,
as the statistical analyses show, these speakers do not treat all CM in (10) in the same way: unlike in
production, in the grammaticality judgment task they prefer English Det mixes where no gender
agreement features are involved because processing this DP is less costly. However, if gender features
appear (i.e. in Spanish Det mixes), they show a clear preference for the enforcement of the gender
agreement mechanism, that is, for the implementation of the AC.
7. CONCLUSIONS AND FUTURE DIRECTIONS
In this chapter, we have provided an analysis of data from two English-Spanish 2L1 bilinguals
growing up in Spain as compared to data from other bilinguals and monolinguals. We have focused on
two core issues that are specific to 2L1 acquisition: language dominance and crosslinguistic influence.
5 These authors specifically argue that bilinguals who code-switch at the societal level may produce code-switches that
differ from those produced and processed by other bilinguals (i.e., non-code-switchers) (e.g. Beatty-Martínez & Dussias,
2017; Guzzardo Tamargo et al., 2016; Valdés Kroff, 2016; Valdés Kroff et al., 2016). Although the populations in these
studies do not involve children in Spain, as it is our case, their Spanish-English bilinguals mostly prefer Spanish-masculine
determiner - English noun CM structures. And this seems to be so for both US east coast bilinguals (who arguably may now
be more English dominant) but also for Spanish dominant Puerto Ricans.
6 The information that is obtained on the representation of language in the mind of the bilingual and on language
competence through the analysis of experimental data complements that obtained from naturalistic data. That is,
experimental data allow us to gather different and complementary information.
25

Our analysis has pointed to how language properties shape the directionality and the effect of
crosslinguistic influence. In particular, Spanish lexical specialization explains that, in the early stages
of English-Spanish 2L1 acquisition, Spanish be the language that constitutes the locus of influence and
that influence has a facilitating effect. This is reflected in how the adult grammatical requirement in
both copula constructions and sentential subjects emerges earlier in the spontaneous production of these
English-Spanish bilinguals as compared to that of English and Spanish monolinguals. Differences with
other bilinguals (e.g. Paradis & Navarro, 2003) could rather be attributed to input differences or a
rather weak command of one of the two languages (Silva-Corvalán, 2014) and not so much to negative
influence from Spanish into English or to lack of crosslinguistic influence.
Language properties and, in particular, Spanish highly grammaticized features, are also behind
the CM preferences that appear in the spontaneous and experimental data of these bilingual children as
well as in that of other bilingual children and adults. As captured under the GFSH and the Gender
Double-Feature Valuation Mechanism, the strength of Spanish gender features makes these bilinguals
prefer the Spanish Determiner in switched DPs and enforce gender agreement between the Spanish
Determiner and the Spanish translation equivalent of the (ungendered) English Noun. Although a
contrast is seen in spontaneous versus acceptability judgment data, the strength of Spanish gender
features is seen not only in the preference for the Spanish Determiner (spontaneous data) but also in the
preference for the [+AC] Spanish Determiner (judgment data; examples 10a versus 10b).
While many future directions may be taken to investigate the outcomes of 2L1 acquisition, we
would like to mention four that are relevant to the outcomes that we have discussed. First, both the
locus and directionality of crosslinguistic influence as well as language dominance should be
investigated with other language pairs where the realization of semantic values (i.e. be versus ser/estar)
takes different realizations. Second, it would be important to carry out analyses of both experimental
and spontaneous data from other language pairs to determine whether constructs such as the
Grammatical Features Spell-Out hypothesis or the Analogical Criterion hold across the board and
26

whether other constructs have to be proposed to deal with alternative scenarios. For instance, what is
the spontaneous output and what are the preferences when mixing a language with a three gender value
DP and a language without grammatical gender or with a two gender value DP (German vs. English or
Spanish as in Klassen, 2016)? Third, in order to complement the results obtained from the analysis of
spontaneous data and off-line experimental data, the outputs and preferences of 2L1 representation and
processing should be investigated using on-line tasks, eye-tracking, ERPs or neuroimaging (as in
Dussias, Valdés Kroff, Guzzardo Tamargo, & Gerfen, 2013). Fourth, language dominance,
crosslinguistic influence and code-switching should be investigated in both contexts of 2L1 individual
bilingualism and 2L1 societal bilingualism.
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