Effects Of Task Repetition,Task Structure And L2 Proficiency On The Linguistic Accuracy And Complexity Of Chinese EFL Learners' Writing Performance

The last decades saw the growing research into task-based language teaching and much attention has been paid to task design for different pedagogical objectives.Research on the effects of task complexity on the language performance is of great pedagogic significance for its role in grading and sequencing tasks more effectively.Despite prolific studies on the effects of task complexity on language performance under the Triadic Componential Framework based on the Robinson's(2007)Cognition Hypothesis,pedagogic task design involving task repetition is rare due to limited research and inconclusive results of its effects on linguistic accuracy and complexity of language performance.Further research find that task complexity manipulated by other task variables such as ±task structure has different impacts on the effects of task repetition in learners' language performance,and the learner variable of L2 proficiency is found to potentially mediate between task complexity and task performance.To date,no study has ever been conducted on how learners of different L2 proficiency respond to the opportunity of repetition when performing tasks with and without a structure in the story.To fill these gaps,the present study is conducted by manipulating task complexity along resource-dispersing variables of ±task structure and the planning condition of ±task repetition,and L2 proficiency at two levels(elementary and intermediate)to address three research questions: 1)What are the effects of task repetition on the linguistic accuracy and complexity of writing production when students perform the ±structured tasks? 2)Are the effects of task repetition on the linguistic accuracy and complexity of writing performance of the ±structured tasks affected by different L2 proficiency levels? 3)Are there interactive effects between task complexity(±task structure and ±task repetition)and L2 proficiency on the linguistic accuracy and complexity of writing performance?Based on the scores of the Oxford Placement Test,twenty-five high school students of elementary L2 proficiency and twenty-five undergraduate students of intermediate L2 proficiency were selected to participate in the study.Within-group homogeneity and between-group difference were assured through normality test and independent T-test.Participants in each group firstly completed two 25-minute writing tasks of different complexity manipulated by ±task structure and repeated the same two tasks with a three-day interval in between.Because of a few absences in the second performance,a total of 160 valid pieces of data were collected and analyzed in terms of linguistic accuracy and complexity.The analyses reveal that:(1)task repetition only has significant effects on the accuracy in terms of errors per T-unit(E/T)and syntactic complexity under the unstructured task.(2)task repetition has no significant effects on language production for both groups of elementary L2 proficiency and intermediate L2 proficiency when they perform the structured task.Under the unstructured task,task repetition has significant effects on the linguistic accuracy and syntactic complexity for learners of elementary and intermediate L2 proficiency,but difference could be found between the two groups.(3)significant interactive effects are found between the task complexity(±task structure and ±task repetition)and L2 proficiency on the writing performance in terms of ratio of error-free verbs(EFV/V).The findings are partially in line with Robinson's(2007)Cognition Hypothesis and it is suggested that task complexity shouldn't be the sole basis for manipulating and sequencing tasks,mediating effects within task complexity factors and between learner factors should be taken into full consideration in order to make tasks achieve the full potential.