This study examines the language use of the conjunctive ending ‘-gillae’. To that end, this study used and looked at a semi-spoken corpus of the speech acts and contextual elements of following clauses according to usage in both declarative and interrogative sentences. Analysis of declarative sentences provided results in the order of explanations, justifications, assertions, attempts, pivots, and excuses. In addition, analysis of the speech acts of interrogative sentences with ‘-gillae’ in terms of not only the question function but also as a rhetorical sentence marker showed that ‘-gillae’ can serve to highlight a question, criticism, complaints, surprise, and exclamation. Furthermore, this paper shows through contextual analysis of both declarative and interrogative sentences that ‘-gillae’ is commonly used in personal and informal discourse when there is a close relationship between the speaker and the listener. However, in interrogative sentences, as criticism and complaints are features of negative speech acts, ‘-gillae’ is more often used in situations where the speaker is of a higher status than the listener. (Yonsei University)