Learners' interaction with lecture materials has remained underexplored despite the growing body of studies on the use of materials. The current study explored the actions EFL learners employed during the use of lecture materials in tertiary classrooms in China through the lens of a transactional view. This empirical study involved forty-two students in two classes as well as two instructors enrolled in the Comprehensive English Course. Qualitative analysis revealed five levels of learner actions during interactions initiated by lectures: awareness, involvement, intervention, creation, and autonomy. The study further highlighted three factors that significantly influence these actions: learners' intrinsic motivation to participate in classroom interactions, discourse space for participation, and the cultural model of learning. Pedagogical implications for enhancing learner autonomy and contributions during lecture materials use were discussed based on results.