The author employs grounded theory to investigate the teaching process of an interdisciplinary general education course at A University as a case. The author finds that under the condition of rather concrete relations between the subject of a major-based course and that of an elected general education course, if the major course is taught with a certain breadth and depth, students would adopt the strategy of using knowledge from their major course in their general education course and using knowledge from their general education course to reflect on the major course. This kind of "two-way insertion" learning model reflects the mechanism of mutual facilitation between major education and general education on the course level. This conclusion has important insights into university general education reforms and general education course building and management. [This article was translated by Jeff Keller.]