Differential Effects of Online Task Planning on Formulaic Language Use and Working Memory over Time

Despite sustained pedagogical emphasis on communicative competence, oral fluency remains a persistent challenge for EFL learners, particularly in task-based speaking contexts involving time pressure. While previous research has examined the effects of task planning on linguistic performance, less attention has been paid to learners’ psychological experiences during task execution and how these experiences interact with cognitive and linguistic resources over time. This study investigates how three online task planning conditions—pressured online planning (POP), unpressured online planning (UOP), and hybrid online planning (HOP)—shape learners’ use of formulaic sequences (FSs), with a focus on both frequency and variation, as well as their relationship with working memory (WM). Ninety Chinese EFL undergraduates participated in an eight-week longitudinal intervention and completed dialogic narrative tasks at pre-test, post-test, and delayed post-test. Quantitative analyses examined changes in FS deployment and exploratory associations with WM capacity. To complement these analyses, stimulated recall interviews were conducted to capture learners’ perceived pressure, emotional responses, and strategic decision-making under different planning conditions. The results reveal condition-sensitive and time-dependent patterns in FS use, with distinct profiles emerging across planning conditions. Interview data suggest that these patterns are closely associated with learners’ psychological regulation under task constraints, particularly their tendency toward risk avoidance, reliance on familiar expressions, and prioritization of fluency under pressure. Together, the findings highlight the importance of integrating psychological perspectives into the interpretation of task-based language performance and offer implications for the design of planning conditions in L2 speaking instruction.