As all Turkic languages, Karaim grammar is characterized by agglutination and vowel harmony. Genetic evidence for the inclusion of the Karaim language in the Turkic language family is undisputed, based on common vocabulary and grammar. Karaim has a historically subject–object–verb word order, extensive suffixing agglutination, the presence of vowel harmony, and a lack of gender or noun classes. Lithuanian Karaim has maintained most of these Turkic features despite its history of more than six hundred years in the environment of the Lithuanian, Russian, and Polish languages.