This study aims to investigate wait-time, more specifically student reaction wait-time, in high school English as a foreign language classrooms with specific regard to two classroom micro-context modes (the classroom context mode and material mode). The data was collected via audio-recordings of classroom interaction in its natural context. The audio-recordings were analyzed using the principles of Conversation Analysis. The analysis of the data demonstrated that the effectiveness of student reaction wait-time is highly related to the current pedagogical goal; if the purpose is to increase learners' involvement in classroom discourse or if it requires analytical thinking, an extended wait-time of three to five seconds is likely to enhance the learning opportunity. However, as a social process, opportunities for learning are likely to be missed if the purpose is to monitor understanding or display answers which are explicitly given in the material that is being used. In this sense, this study has implications for studies on wait-time, foreign language classroom interaction, teachers' interactional competence, and foreign language learning contexts in general.