L1 and L2 use in pre-task planning and task repetition: The role of proficiency

Abstract This is an investigation of the interplay between collaborative pre-task planning language, task repetition, and L2 proficiency in oral narrative task performance. A total of 128 EFL learners engaged in paired collaborative planning under one of four conditions: L1, L2, combined L1–L2, and no planning. Subsequently, each participant individually completed an oral narrative task four times. Task performance was analyzed for utterance fluency, and L2 proficiency was measured using an elicited imitation task. Results indicated that while the language that learners used to plan did not significantly affect fluency, its interaction with learner proficiency was crucial. More proficient L2 learners benefited most from L1 planning, particularly in formulation and monitoring processes, whereas learners with lower proficiency struggled in this condition. Task repetition also enhanced fluency across all conditions, partially mitigating initial proficiency-related differences. The study highlights the importance of learners’ individual differences, in this case proficiency level, in task-based language teaching. Findings challenge a one-size-fits-all approach to task implementation and support the judicious incorporation of L1 during pre-task planning, particularly for more proficient learners.