The present study was conducted within the framework of sociocultural theory to examine the effect of flipped instruction on Iranian English as a foreign language (EFL) learners’ development of conditional sentences. The study benefited from quantitative methodology within which 60 intermediate Iranian male EFL learners who were checked for their language proficiency by an Oxford Quick Placement Test (OQPT) to meet the homogeneity assumption were selected and given a pre- and post-test as well as a delayed post-test on conditional sentences. Half of the learners formed the experimental group and the remaining participants were assigned to the control group. The flipped instruction occurred through WhatsApp and was amplified by face to face discussions on the linguistic materials. Online learning environment armed the learners with the formal instruction of conditional sentences while the in-class time was devoted to tap into meaningful interaction for internalizing the previously-uploaded audio and video grammar tasks. The learners in the control group were provided with direct instruction by using traditional whiteboards. Results revealed that the experimental group, receiving flipped teaching, outperformed the control group that received conventional type of grammar instruction. Moreover, the use of flipped model resulted in significant improvement in learning and retention of conditional sentences. Findings also demonstrated that learners benefited from flipped-taught grammar augmented through feedback in the face-to-face classroom, which acts as the mediator between the teacher and the learners. It can be strongly recommended that teachers can take advantage of flipped instruction in providing effective instruction of language skills and sub-skills and facilitate the learning process for the learners as well.

中文翻译：

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翻转的课堂对第二语言学习者发展和语法知识保留的影响

本研究是在社会文化理论的框架内进行的，以检验翻转教学对伊朗英语作为外语（EFL）学习者条件句发展的影响。这项研究得益于定量方法，其中选择了60名通过牛津快速分班考试（OQPT）检查其语言能力以符合同质假设的伊朗中级男性EFL学习者，并进行了前测和后测以及推迟对条件句的后测。一半的学习者组成实验组，其余的参与者被分配到对照组。翻转的指令是通过WhatsApp进行的，并且通过与语言材料的面对面讨论而得到放大。在线学习环境为学习者提供了条件句子的正式指导，而课堂上的时间则投入到有意义的互动中，以实现先前上传的音频和视频语法任务的内部化。对照组的学习者可以使用传统的白板直接学习。结果显示，接受翻转教学的实验组优于接受常规语法教学的对照组。此外，翻转模型的使用大大提高了条件句的学习和保留。研究结果还表明，通过面对面课堂中的反馈，学习者从翻转教学中受益，这是教师与学习者之间的中介。