This study sought to investigate the effect of the two input types interactionally modified input (IM) and textual input enhancement (TIE), the impact of a commonly used learning styles taxonomy as the Visual, Auditory and Kinesthetic learning styles (VAK) by itself as well as the interactional effect of perceptual learning styles and input types on the causative construction development of EFL learners. To this end, 120 female Iranian EFL learners from three language schools in Tehran participated in this research and were divided into two experimental groups of 60. The study adopted a pretest-posttest design and learner’s grammar knowledge was measured before and after providing them with instructional treatment through IM input and TIE techniques. The data were analyzed through a two-way ANOVA. The results of the study indicated that IM input was significantly more effective than TIE in promoting the participants' knowledge of the target structure. The comparison of the posttest means scores also revealed that the VAK style was not an influential factor in second language learners’ target form knowledge, while a significant interaction between input type and learning styles turned out to have a beneficial effect if they synchronize in classrooms. تفاصيل المقالة