Prior research on classroom interaction has investigated how the teacher's feedback turn following students' responses can be used to transform students' turns into academic expressions during whole class discussions. Nevertheless, more empirical studies are needed to explore how teachers' translanguaging practices can play a role in shaping students' contributions into pedagogical opportunities for introducing academic terminologies in English-Medium-Instruction (EMI) classrooms. Adopting translanguaging as an analytical perspective, this study explores how an EMI history teacher deploys available linguistic and multimodal resources to connect students' responses with academic concepts and terminologies. The study draws its data from a larger linguistic ethnographic project that took place in an EMI secondary history classroom in Hong Kong. The classroom interaction data is examined using Multimodal Conversation Analysis, and this analysis is further triangulated with video-stimulated-recall-interviews that are analysed using Interpretative Phenomenological Analysis. This paper argues that the EMI teacher's translanguaging practices facilitate the process of transforming student contributions into academic terminology and concepts. The process of deploying translanguaging for transforming student contributions highlights translanguaging as an important component of the teacher's classroom interactional competence for constructing new configurations of language practices and achieving specific pedagogical purposes.