There were two dialects, Columbia (Sinkiuse, Columbian) and Wenatchi (Wenatchee, Entiat, Chelan). Wenatchi was the heritage language of the Wenatchi, Chelan, and Entiattribes, Columbian of the Sinkiuse-Columbia.
Pauline Stensgar, who died on May 2, 2023 at age 96, is reported to have been the last known fully fluent speaker.[2]
Phonology
Phonological inventory of the Columbia-Wenatchi dialect:
The three vowels in Moses-Columbia are /i/, /a/, /u/. They are sometimes transcribed as [e]; /i/, [o]; /u/, and [æ]; /a/, and could also tend to sound unstressed, almost as a schwa sound, /ə/.
Czaykowska-Higgins, Ewa and Paul Proulx. 2000. "REVIEWS - What's in a Word? Structure in Moses-Columbia Salish". International Journal of American Linguistics. 66, no. 3: 410.
Kinkade, M. Dale. Dictionary of the Moses-Columbia Language (Nxaʔamxcín). Nespelem, Wash: Colville Confederated Tribes, 1981.
Mattina, Nancy. 2006. "Determiner Phrases in Moses-Columbia Salish". International Journal of American Linguistics. 72, no. 1: 97.
Willet, Marie Louise. 2003." A Grammatical Sketch of Nxa'amxcin" PhD Thesis, University of Victoria.