Content-language integration has been perceived to be an effective approach in second and foreign language learning. However, it can be challenging to implement in content classes, especially in science classrooms. Researchers have suggested using tasks and games to help design diverse opportunities for language and content learning; in particular, a game-mediated dual learning model was proposed to guide the development of instructional activities. The present study aims to share the empirical results of a qualitative-driven research study guided by the aforementioned model, with a focus on participants' language production. Using language-related episodes as a unit of analysis, this study explored how secondary school English language learners collaboratively participated in game-mediated activities in a science class.