Exploring Style Shifting and Planning Variability in Past-Tense Use: A Case Study of an Intermediate L2 Learner

Abstract

This study investigates style shifting in second language (L2) acquisition by focusing on the impact of planning time on the accuracy of the past-tense morphology in narrative discourse. Grounded in theories of cognitive processing and variability in L2 performance, this study examines the acquisition experience of an intermediate L2 English learner to explore variability in the use of three past-tense morphemes: regular past tense (e.g., walked), irregular past tense (e.g., went), and past copula (e.g., was). Data were collected using three tasks: a written narrative and two oral narratives designed to elicit varying degrees of planning time. The results revealed significant style shifting, with regular past-tense forms showing the greatest variability and declining accuracy within the reduced planning time. The irregular past-tense forms remained relatively stable, whereas copular past-tense accuracy exhibited moderate variability. Statistical analyses confirmed a significant effect of task type on regular past tense accuracy (F(2, 36) = 8.76, p < 0.01), with post-hoc tests indicating higher accuracy in the planned tasks. These findings highlight the cognitive demands of rule-based morphology for spontaneous speech. This study offers practical implications for L2 instruction, emphasizing the importance of pre-task planning, targeted feedback, and metacognitive strategies in enhancing learners’ grammatical accuracy. As this study focuses on a single learner, it provides detailed insights into individual variability, although further research with a larger sample could provide more generalizable findings.