added a research item
This paper offers new evidence from Stau, Geshiza, and Khroskyabs to address the question of directionality in valency-changing derivations in Sino-Tibetan. Examining Stau, Geshiza, and Khroskyabs causative and an-ticausative verb stem pairs adds to the evidence that in Proto-Sino-Tibetan a number of intransitive stems are derived from transitive stems, in some cases as the result of *N-prefixation, and in other cases from voicing alternation independent of *N-prefixation. In addition, the proto-sigmatic prefix (*s-) does not cause devoic-ing in Stau, Geshiza, and Khroskyabs, but rather often undergoes voicing assimilation, and has more than just a causativization function. Furthermore, by looking at Gyalrong, Minyag, Tangut, Middle Chinese, and Old Chinese we emphasize that there is no synchronic evidence to support devoicing induced by *s-, nor is there historical evidence to support the claim that *s-caused devoicing in Proto-Gyalrongic, and even genetically deeper stages.
In this paper, we propose that in Stau (Rgyalrongic, Sino-Tibetan) there is a system of four vowel pairs (/i/-/ə/, /e/-/ɛ/, /æ/-/ɑ/, /u/-/o/) that undergo regressive vowel harmony. This system of vowel harmony produces root morpheme forms such as [æCæ] and [ɑCɑ], whereas forms like [æCɑ] or [ɑCæ] are remarkably absent. Vowel harmony is also observed when combining morphemes to create complex words. Unambiguous cases show that the vowel of the first morpheme assimilates to the vowel of the second (e.g. /æCɑ/ → [ɑCɑ]), if the vowels of the two morphemes belong to the same vowel pair set (e.g. /æ/-/ɑ/). At the same time, there are several situations where vowel harmony is consistently not observed. Notable among these blocking mechanisms are lexemes that contain semantically-heavy first syllables. In this situation, we observe the interplay of semantics and phonology. Analysis of the vowel harmony system in Stau yields a way to measure the distance between morphemes.
This paper presents the first documentation and analysis of a typologically remarkable process of verbal triplication in the Stau language (Sino-Tibetan). Moreover, Stau's triplication of verbs to index multiple agents (S/A) is also used pragmatically to highlight those agents. Stau's verbal triplication, although unique in many regards, falls into a broader typological linguistic pattern of iconicity, demonstrating that there is often a strong tie between form and function.