Proto-Tai language

Proto-Tai is the reconstructed common ancestor (proto-language) of all the Tai languages, including modern Lao, Shan, Tai Lü, Tai Dam, Ahom, Northern Thai, Thai, Bouyei, and Zhuang. The Proto-Tai language is not directly attested by any surviving texts, but has been reconstructed using the comparative method. It was reconstructed in 1977 by Li Fang-Kuei and by Pittayawat Pittayaporn in 2009.

The following table shows the consonants of Proto-Tai according to Li Fang-Kuei's A Handbook of Comparative Tai (1977), considered the standard reference in the field. Li does not indicate the exact quality of the consonants denoted here as tɕ, tɕʰ and dʑ, which are indicated in his work as č čh ž and described merely as palatal affricate consonants.

The table below lists the consonantal phonemes of Pittayawat Pittayaporn's 2009 reconstruction of Proto-Tai (Pittayaporn 2009:70). Some of the differences are simply different interpretations of Li's consonants: the palatal consonants are interpreted as stops, rather than affricates, and the glottalized consonants are described using symbols for implosive consonants. However, Pittayaporn's Proto-Tai reconstruction has a number of real differences from Li:

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