This study analyzes the syntactic and lexical complexity of English speaking and writing among Korean university students, exploring how these linguistic complexities correlate with English proficiency. To address this, a systematic meta-analysis of recent literature on this topic was conducted using a large-scale learner corpus. Fourteen metrics were applied to evaluate the syntactic complexity of 244 English learners. The results showed that coordination structure scores were higher in speaking activities, whereas subordination structure scores were higher in writing activities. Lexical complexity was measured in terms of diversity (vocd-D, MTLD), density (verb density, noun density), and sophistication, with notable differences observed depending on the task type. Specifically, writing activities exhibited higher lexical diversity and verb density, while speaking emphasized noun density and lexical sophistication. The study found that syntactic complexity (measured by MLT, CPT, CPC) and lexical complexity (measured by verb density) are significant predictors of English speaking proficiency. These findings were derived by synthesizing and analyzing recent studies that examined subtle differences in syntactic and lexical complexity using learners' data involving different task types. This research contributes to a deeper understanding of the characteristics of English speaking and writing skills among Korean learners, offering valuable insights for the development of English curricula and strategies to enhance learners' language abilities. In essence, this study provides concrete guidelines to support language development for English educators, thereby increasing the applicability of these findings in educational settings.
Ⅰ. Introduction
Ⅱ. Literature review
Ⅲ. Research method
Ⅳ. Results
Ⅴ. Discussion and Conclusion
Work Cited