Exploring the effects of planning conditions and peer familiarity on Chinese EFL learners’ argumentative writing

Despite numerous studies on the effect of task planning on L2 writing, little research has examined the combined effects of pre-task planning (PTP) and (pressured and unpressured) online planning (POP and UOP). This study, therefore, investigated the effects of the combined planning conditions and peer familiarity on Chinese EFL learners' argumentative writing. Sixty-four Chinese EFL participants were assigned to four groups: 2 planning conditions (i.e., PTP + POP vs. PTP + UOP) × 2 levels of peer familiarity (i.e., ± familiar). With a 14-min collaborative prewriting discussion, the PTP + POP groups performed the argumentative writing task within 27 min, while the PTP + UOP groups finished the task at their own pace. MANOVA analyses revealed the following findings: (1) the PTP + UOP groups outperformed their counterparts in analytic rating, syntactic complexity, accuracy, and lexical complexity; (2) the PTP + POP groups enhanced fluency and lexical complexity; (3) unfamiliarity seemed to foster lexical complexity and fluency; (4) interactional effects between planning conditions and peer familiarity were observed in syntactic complexity, lexical complexity, and fluency. These findings provide novel evidence regarding the effects of planning conditions and peer familiarity on L2 learners’ writing task performance.