The Turkish language in diaspora is in process of change due to different language constellations of immigrants and the dominance of majority languages. This led to a great interest in various research areas, particularly in linguistics. Against this background, this study focuses on developmental change in the use of adverbial clause-combining constructions in Turkish-German bilingual students’ oral and written text production. It illustrates the use of non-finite constructions and some unique alternative strategies to express adverbial relations with authentic examples in Turkish and German. The findings contribute to a better understanding of how bilingual competencies vary in expressing adverbial relations depending on language contact and extra-linguistic factors.