Phonetic Changes of Eastern Yugur Language-Case Study of Vowel/a/

As one of the two native languages of Yugur Nationality, Eastern Yugur language is already an endangered language and is still constantly changing. In order to get a better understanding of the nature of Eastern Yugur language for the sake of both language protection and pedagogy, the article focuses on vowel /a/ and discusses the changes of this very vowel: in unstressed syllable /a/ is reduced, omitted and devoiced, and some of these changes have been reflected in the spelling. Consonants [t integral, t integral(h)] can trigger diphthongization of /a/, but the reasons behind this is the influence of Chinese upon Eastern Yugur language through language contact.