Tarihî Türk Lehçelerinden Türkiye Türkçesine -dır/-dur (

Abstract: Auxiliary verb tur-, which was used in terms of Old Turkish, Middle Turkish, and historical process of suffix -DIr/-DUr, that became an enclitic structure beginning from Kipchak Turkish and Old Anatolian Turkish, and functions in modern Turkey Turkish, is the main subject of this article. This grammatical structure, which is determined in all terms of Turkish language, was examined by linguists in different forms. But this subject was revealed with various terms in grammar books and dictionary of grammar terms; various functions of verb could not been brought up sufficiently. These problems are emphasized in the article; auxiliary verb tur- and the copula -DIr/-DUr is worked with examples in process of historical Turkish language.