Input-induced Variation in EFL Learners’ Oral Production in Terms of Complexity, Accuracy, and Fluency

Researchers have extensively studied phenomena that affect a second language learner’s oral production while there is scant evidence about input-related factors. Accordingly, the present study sought to investigate how variation in oral production is caused by the input they receive from different course materials. To this end, the study included a micro-evaluation study of three course materials and a quasi-experimental pretest-posttest design with three groups of participants (N = 72) instructed with three different course materials (New Headway, American English File, and Top Notch & Summit). Speech samples elicited through picture-cued oral narrative tasks at three data collection times were quantitatively assessed for complexity, accuracy, and fluency (CAF). A one-way Multivariate Analysis of Variance (MANOVA) was used to compare the means of CAF scores. With respect to pretest-posttest differences on measures like the average number of subordinate clauses per AS-unit for grammatical complexity, “D” index for lexical complexity, percentage of error-free clauses for accuracy, and number of dysfluencies for fluency, the results indicated that different course materials have insignificant effects on the variation in grammatical complexity but a clear effect on the variability in lexical complexity, accuracy, and fluency. Micro-evaluation of the three course materials revealed that this variability might well be attributed to the characteristics of the speaking tasks in the textbooks. One important implication is that EFL materials developers can provide the learners with the experience of speaking tasks with particular features if they want to promote gains in a special dimension of oral performance (e.g., fluency).