A dynamic case study on the development of syntactic complexity of second language learners’ written English

This study investigates the relationships between syntactic complexity indices across different dimensions and proficiency levels in second language (L2) writing. Using the Complex Dynamic Systems Theory as a framework, the study analyzed 72 essays from six first-year non-English majors at a Chinese university. The analysis reveals a complex interplay between measures of syntactic complexity at the sentence, clausal, and phrasal levels. Higher proficiency learners show greater syntactic complexity, especially at the clause and phrase levels, while lower proficiency learners show more variability at the sentence level. The study also identifies non-linear and dynamic patterns of evolution of syntactic structures, highlighting significant fluctuations indicative of both progression and regression in learners’ syntactic complexity over time. The findings underscore the dynamic nature of L2 development and suggest that a multidimensional approach is necessary for a better understanding of syntactic complexity in L2 writing.