Effects Of Task Complexity On English Majors’ Oral Performance

In the field of task-based language teaching,more and more studies used tasks of different complexity to investigate its impact on learners’ second language performance,and its impact on learners’ language production remains controversial.Moreover,domestic research mainly focuses on written language output.There are relatively few domestic studies on the influence of task complexity(in the dimension of resource directing)on learners’ oral output.This study aims to provide empirical basis for curriculum design and task design.It also can help predict learners’ language performance through the design of task complexity.Based on Robison’s Cognition Hypothesis,this study adopted SWEECL(2.0)corpus compiled by Wen Qiufang et al.(2008).The oral corpus of the candidates was selected from the oral test of TEM-4 in 2005(seen Appendix1,2 and 3),and the 15 th group in the corpus was adopted by random sampling.This group consists of 31 students,all of them are 18-22 years old.They all completed three tasks in the examination,namely: Retelling the story,Talking on a given topic(perspective-taking),and Role-play(reasoning of opinions).The time of each task is controlled within three minutes,and the examinee’s test audio has been transcribed into text corpus.The complexity of these three tasks was increasing in the dimension of reasoning and perspective-taking.These three tasks are the most commonly used oral tasks for Chinese learners,but their effects on oral performance have seldom been studied.Therefore,it is necessary to investigate the effects of these tasks on different aspects(accuracy,complexity and fluency)of oral performance and development.For the analysis of voice data,Praat was used to analyze Speech rate,Articulation rate,Mean length of run,Average length of pause and Repairs of oral fluency.As for the transcribed text,L2 Syntactic Complexity Analyzer was used to analyze the indexes(Mean length of clause,Mean length of T-unit,Clause/Sentence,Complex nominal/T-unit)of syntactic complexity.The lexical complexity was analyzed by L2 Lexical Complexity Analyzer,which includes Lexical sophistication1,Lexical sophistication 2,Type/token ratio and Corrected Type/token ratio.The accuracy of oral English was processed by Grammarly,the index of Error-free T-units is included.The data obtained were performed in SPSS 21.0 to conduct a data analysis and One-way ANOVA was used.The findings are summarized as follows:(1)Task complexity has a significant impact on the accuracy of oral performance(P =.000 <.05).When task complexity increases,learners pay more attention to content,and oral output is more accurate.(2)Task complexity has a significant impact on Lexical complexity1(P =.000<.05),Lexical complexity2(P=.000)and Corrected Type/token ratio(P =.000).The increase of task complexity can promote the increase of these indicators,but no significant difference was found about the Type/token ratio.At the syntactic complexity level,there was no significant effect of task complexity on each index.(3)Task complexity has a significant effect on speech rate(P =.000),articulation rate(P =.000),Mean length of run(P =.000)and Repairs(P=.000)of oral fluency.With the increase of task complexity,learners’ oral fluency decreases as a whole.The results further confirm Robison’s Cognition Hypothesis.Increasing task complexity in resource directing lead to more accurate and complex(mainly reflects in lexical complexity)output,while higher cognitive requirements lead to less fluent production.The above findings have some implications for task design and curriculum design.Firstly,Teachers can improve learners’ oral performance effectively by manipulating task complexity.At the same time,manipulating task complexity can also give some enlightenment to the designer of large-scale oral test and curriculum.