The Effects of Task Variation on the Accuracy and Complexity of Iranian EFL Learners’ Oral Performance

Task variation is an integrative method aiming at the importance of learner-to-learner interactions in a wide range of learning contexts and fostering authentic use of language and meaningful communication. This study investigated the impact of task variation on the accuracy and complexity of Iranian EFL learners’ oral speech. In so doing, 80 intermediate EFL learners, majoring English at the Islamic Azad University, Tonekabon branch, were randomly assigned to four equal groups based on their scores on OPT: Experimental Group 1 (EXG1), treated by a variation of three tasks, i.e., dialogue completion, group dialogue, and dialogue unscrambling; Experimental Group 2 (EXG2), treated by a variation of two tasks including dialogue completion and dialogue unscrambling; Experimental Group 3 (EXG3), instructed through a single task (dialogue unscrambling), and the Control Group (CONG), instructed through teacher routine or conventional method. The speaking part of the Preliminary English Test (PET) was administered to the groups as a pretest and posttest. The four groups received their required instructions for ten sessions. The results of the ANOVA and Post Hoc analyses indicated that the three task variations were effective on two features of accuracy and complexity. It was also revealed that the EXG1, treated through a variety of three tasks, outperformed the other three groups in terms of accuracy and complexity. Task variation is hence advised to be incorporated in EFL teaching and testing contexts as a useful tool to improve learners’ oral performance on accuracy and complexity.