From a dynamic systems theory perspective, this study investigated the development of complexity, accuracy and fluency (CAF) in five undergraduate multilingual learners' L1 (Chinese), L2 (English) and L3 (French) writing throughout an academic year. Via detailed analysis of the quantitative data, this study aims to longitudinally depict the dynamic and interactive development of CAF in multilingual learners' writing. Results show that the developmental patterns of CAF in multilingual learners' (especially each individual learner's) L1, L2 and L3 writing were characterized by non-linearity, recurrent and elusive increase and backsliding, emergent and constant changes, chaotic iteration, etc. Results also demonstrate that CAF components were integratively and interactively correlated with each other in multilingual learners' writing over time. The findings hold some implications for theories and methodologies of multilingual acquisition/development studies.
Dynamic Systems Theory, Complexity, Accuracy, Fluency, Multilingual Development.