Thesis is dedicated to the manifestation of the Turkish language reform using the methods od corpus linguistics. Aim of the thesis is to find out for the selected pairs of original Ottoman words and their Turkish equivalents to what extent are both variant sused in contemporary Turkish texts and to assess if any of the pairs was not functionally differentiated and if the choice was influenced by any contextual factors. In the thesis, we examine the frequency of adjectives, whether one of the variants is more or less used; Ottoman variants are used more often. In the case of pairs, we examine the frequency and preference of variants in types of text, in most cases one variant is preferred in all types of text, but some of them were differentiated. In the case of the pair siyasal and siyasi, on 500 randomly generated sentences, we examine possessors and adjective suffixes in the sentence bound to the possessor, as well as adjectives with the suffix -sel and -i, which are not bound to it and are in the sentence. In the first case, in most cases, the suffixes are matching, in the second case, there suffixes are matching with the word siyasal, but not with the word siyasi. Key words Turkish language reform, corpus linguistics, adjective suffix -sel, adjective suffix -i, language puris
