My advisee Seo Hyun Park and I will present a paper at the Annual Meeting of the American Association for Applied Linguistics. We examine how students initiate talk about Dutch grammar and how the instructor produces non-minimal post-expansions, using talk, gesture, and writing on the blackboard to construct mini grammar lessons. The instructor’s expansion is witnessably successful in one of the sequences, unsuccessful in the other. In presenting our analysis of these two sequences, we show how linguistic and conversation-analytic approaches to language must be combined in these instances to answer the core question of CA, “Why that, in that way, right now?”.