The Kwaya language is spoken in the area of Musoma and its southeastern area, Mara Region of Tanzania. It belongs to the Nyanza-Suguti group of the lacustrine Bantu languages (Nurse and Phillipson, 1980).
The area where Kwaya people live is divided into four, but the degree of language differences among the four areas is not known. The main informant for this study is from Etaro Village in one of the four areas, as is the supplemental informant. Data from a third informant is used, when necessary. He comes from Nyakatende, a different area from the first two informants.
Tonal fluctuation is one of the characteristics of this language. The fluctuations are sometimes observed among informants. The fluctuations are found even on a word uttered by the same informant when spoken on a different occasion. The fluctuations are also found in word forms of some conjugations, though this is not an object of this paper. These facts may suggest that this language is heading towards losing its tonal distinction.
Though the above fluctuations exist, it is clear that the tonal patterns of nouns are divided into two distinctive groups. That is, one has a high tone in the noun stem while the other does not. The position of the high tone is predictable from the number of syllables in the stem. Tonal patterns of adjectives are also divided into two distinctive groups.
In Chapter 1, an outline of the Kwaya language and the preceding studies are described. In Chapter 2, tonal patterns of nouns and infinitives in isolation are discussed. From the tonal characteristics of infinitives, so-called post-accent is supposed and both infinitives and nouns are divided into two tonal groups, one with a post-accent and another without a post-accent Furthermore, tone melody (TM), association convention (AC) and tonal behavior on the final syllable are discussed. In Chapter 3, tonal patterns of copulative sentences (copula + noun) are discussed from two viewpoints, i.e., vowel contraction or vowel omission between the copula and the prefix of the following noun. Here, a post-accent is also supposed on the copula. In Chapter 4, tonal patterns of demonstratives are discussed. Especially, the underlying specification of the prefix is non-accented, and the H-insertion on the prefix is supposed when a demonstrative modifies a noun. In the insertion, it is discussed that a post-accent is not permitted. In Chapter 5, tonal patterns of adjectives are discussed. As well as the demonstratives, the H-insertion on the initial vowel is required when it modifies a noun. The tonal patterns of stems and their derivations are also discussed from a viewpoint of dialectal differences, and the adjectives are also divided into two tonal groups by the presence or absence of a post-accent. In Chapter 6, a summary of the analysis is described. That is, Kwaya is a language distinguished only by the presence or absence of a post-accent. Finally, similarities between Japanese dialects and this language are discussed.