Investigating English as a foreign language (EFL) students’ writing performance is a continuing concern within the field of research on writing. The present contribution scrutinizes style-shifting in EFL students’ assignments through an examination of the nature of their image-schemas of different types of academic genres, the most prominent factors that may affect the structure of these image-schemas, and the effect of the insufficient structure of these image-schemas, if any, on students’ written assignments. A number of semi-structured interviews were conducted and sample texts were analyzed, following a content analysis approach integrated with a grounded theory approach. The study shows that EFL students’ image-schemas seem to be interactive, interpretive, and dynamic in nature. It also shows that the structure of these image-schemas can be influenced by several cognitive, affective, social, and contextual factors. Significantly, the insufficient structure of these image-schemas may lead EFL students to shift their style locally and globally.