large and fine-grained complexity measures and writing quality among iranian efl learners

In recent years, there has been extensive research on syntactic complexity in l2 writing. however, a significant research gap remains in understanding the specific association between syntactic complexity measures and the quality of writing among adolescent learners of english as a foreign language (efl). this research study aimed to bridge this gap by examining the connection between syntactic complexity measures and writing quality in 146 argumentative essays by iranian-speaking learners of english as a foreign language, as assessed by human raters. syntactic complexity measures were analyzed through computer programs called l2sca and taassc. two regression analyses were run to assess the relationship between the predictor and outcome variables. the results revealed that syntactic complexity model explained 35.6% of the variance in the outcome variable (students’ writing scores) with “dependent clauses per t-unit”, “mean length of t-unit”, “mean length of clause”, and “complex nominals per t-unit” as the strongest predictors. also, the combined model accounted for 44.1% of the variance in the outcome variable. the findings from this research offer valuable insights into writing assessment and pedagogy, enabling language educators to design more effective instructional strategies tailored to the specific needs of this learner group.