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Spelling variants and varieties include the following (Sidwell 2005:11).
Kui
Kuy
Kuay
Koay
Souei. The term "Souei" is also applied to other groups, such as a Pearic community in Cambodia.
Yeu
Nanhang
Kouy. A textbook in French is published for this variant (Parlons Kouy).
Dialects
Van der haak & Woykos (1987-1988) identified two major Kui varieties in Surin and Sisaket provinces of eastern Thailand, Kuuy and Kuay. Van der haak & Woykos also identified the following divergent Kui varieties in Sisaket Province, Thailand.
A variety of Kui/Kuy called Nyeu (ɲə) is spoken in the villages of Ban Phon Kho, Ban Khamin, Ban Nonkat, Ban Phon Palat, and Ban Prasat Nyeu in Sisaket Province, Thailand. The Nyeu of Ban Phon Kho claim that their ancestors had migrated from Muang Khong, Amphoe Rasisalai, Sisaket Province.
In Buriram Province, Kuy is spoken in the 4 districts of Nong Ki, Prakhon Chai, Lam Plai Mat, and Nong Hong (Sa-ing Sangmeen 1992:14). Within Nong Ki District, Kuy villages are located in the southern part of Yoei Prasat (เย้ยปราสาท) Subdistrict and in the western part of Mueang Phai (เมืองไผ่) Subdistrict (Sa-ing Sangmeen 1992:16).
Phonology
The following is the phonology of the Kui (Surin) language:
The following list of Kuy village locations in Sisaket Province is from Van der haak & Woykos (1987-1988:129). Asterisks (placed before village names) denote ethnically mixed villages, in which ethnic Kuy reside with ethnic Lao or Khmer.
Yantreesingh, Pailin (1980). The phonology of the Kuay language of Suphanburi with comparison to the Kuy language of Surin. Nakhon Pathom: University.
References
Mann, N., & Markowski, L. (2004). A rapid appraisal survey of Kuy dialects spoken in Cambodia. Chiang Mai: Dept. of Linguistics, Graduate School, Payap University.