effect of using first language by iranian efl learners in task preparation on their speaking accuracy, fluency, and complexity

The current inquiry aimed to examine the effect of the first language by iranian learners of a foreign language (efl) in task preparation on their speaking accuracy, fluency, and complexity. for this purpose, 40 iranian efl learners at the intermediate level were selected based on a placement test and divided into two equal groups. then, the speaking fluency, accuracy, and complexity test was administered as the pretest. the treatment lasted for five sessions of 60 minutes. in these sessions, the learners did oral opinion tasks. in the first group, participants were supposed to spend 10 minutes cooperating with a partner to read a proposed problem, discuss their solutions, and jot down by in a planning sheet. within 10 minutes, they prepared for the task using only their l1 (persian) to improve both their speaking and writing skills. following that, the participants were separated into various rooms and were given two minutes to plan the task in english prior to doing the task. in contrast, the second group completed the planning sheet and prepared the task in english as their second/foreign language. the instruction lasted five sessions. at the final session, the speaking fluency, accuracy, and complexity posttest were conducted. the effects of the task planning conditions were analyzed and compared during and after the task performance. the data were analyzed via ancova. the findings indicated that using l1 by iranian efl learners in task preparation significantly affected speaking accuracy, fluency, and complexity. finally, the pedagogical and theoretical implications of the study are provided.