摘要:AbstractWritten corrective feedback (henceforth CF) has been an issue of substantial controversies and debates. Although the focus of current CF studies has primarily been on grounding the value of focused CF, evidence on the benefits of unfocused CF is still limited. Moreover, it is essential to explore whether and how correction impacts the complexity of students’ writings to diminish the prospect that CF accuracy improvement is actually caused by evading more complex language use. The current study examined the effectiveness of unfocused written CF on the syntactic and lexical complexity of students’ writing. The participants were 30 homogeneous advanced learners from an English Institute located in Yazd; they were divided into experimental and control groups. Both groups were asked to write 10 compositions during the course but only the experimental group received unfocused CF for each essay. A computerized text analysis (Analyzer) was used to measure the linguistic properties of the written compositions. Syntactic complexity (ratio of subordination and average sentence length of the written texts) and lexical complexity (lexical diversity and lexical density) were calculated by the program. Using Multivariate analysis revealed a significant gain for both syntactic and lexical complexity in the experimental group. The paper concluded with theoretical and pedagogical implications of unfocused written CF for future research and classroom use.