Investigating The Main and Interaction Effects of Task Manipulation and Learner Variables On Iranian Learners’ Writing Skill

Task features and learner variables are believed to play an important role in language outcome. Thus, the present factorial between-subject study set out to determine the main and interaction effects of task manipulation in terms of intentional reasoning and planning time and learner variables with regard to language learning aptitude on Iranian intermediate learners’ written performance in letter writing tasks. Lexical and syntactical complexity and also accuracy were the linguistic elements measured as dependent variables in the writers’ performance. First, the participants were randomly divided into three experimental groups; each group included 70, 76, 80 participants respectively. Then, they were assigned to planning and no-planning groups within each experimental group, and there were the same number of high-aptitude and low-aptitude participants in each planning group. Three letter writing tasks with different degrees of reasoning demands (low, medium, high) were designed, and each experimental group received one of these tasks. The ones in planning groups were also given 10 extra minutes for planning before performing the tasks.