Abstract
This study aimed to investigate the effectiveness of using ChatGPT, a language model, in teaching fixed expressions and conversational strategies to improve Iranian EFL learners’ speaking skills. The study employed a pretest-posttest design, with 55 participants from two intact conversation classes selected through a convenience sampling aged between 20 and 32 intermediate EFL learners. Before the intervention, a pretest was administered. The classes started with teaching the 'Evolve 3', including related vocabulary and structures. The participants practiced using fixed expressions and conversational strategies in pairs, utilizing ChatGPT for comprehension, explanation, and additional examples. Further, the instructor emphasized the function and importance of these expressions. The posttest results were analyzed using t-tests, which showed a significant improvement in the participants' speaking skills after the intervention. The findings indicated that integrating ChatGPT into language instruction can be an effective method to teach fixed expressions and conversational strategies, leading to improvements in English learners' speaking skills. The use of a language model like ChatGPT provides students with immediate feedback, comprehension support, and additional examples, which can greatly facilitate their learning process. It provides insights and recommendations for educators and curriculum designers to explore innovative ways of integrating AI-powered language models into language teaching methodologies