Document Type : Research article


1 Department of English Language Teaching, Faculty of Literature and Humanities, Imam Khomeini International University, Qazvin, Iran

2 Department of English Language, Faculty of Humanities, Lorestan University, Khorramabad, Iran


Syntactic complexity (SC) is an important construct for gauging L2 writing proficiency. Previous studies, including Biber et al. (2016) and Dong et al. (2023), have largely focused on syntactic elaboration and disregarded syntactic diversity. This study investigates how academic writing proficiency is associated with SC, through an evaluation of both the variety and elaboration of sentence structures. To that end, a corpus of the abstract sections of MA theses, PhD dissertations, and empirical research articles in applied linguistics produced by Iranian English medium academic writers was compiled. Drawing on automated text analysis tools (Stanford Core NLP and L2 SC analyzer), we measured syntactic elaboration and diversity of the texts written by three distinct sets of academic authors. The results indicated that phrasal and global measures of syntactic elaboration significantly predicted academic writing proficiency in both novice and expert writers. The results of the second phase of the study indicated that the incorporation of syntactic diversity measure considerably increased the predictive power of the model. The pedagogical implications of the findings for academic writing instruction through consciousness-raising activities for both novice and expert writers are discussed.


Main Subjects

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