The effects of task complexity and collaborative writing on L2 syntactical complexity development: A self-determination theory perspective

Collaborative writing is well acknowledged as an effective pedagogical practice facilitating L2 learners’ writing performance and motivation. Yet, little is known about whether collaborative writing with various cognitive demands can contribute differently to L2 writers’ syntactical complexity development in their later individual writing. To address such research gap, this research investigated how task complexity and collaborative writing would impact L2 learners’ syntactical complexity development under the guidance of Self-Determination Theory (SDT), with a specific focus on the emotional experiences in explaining the learning processes in collaborative writing. 126 Chinese post-graduate EFL learners were assigned to four conditions: three experimental groups and one control group. Experimental group participants received three rounds of collaborative writing interventions varying in different cognitive demands, manipulated through +planning time, and +few elements, while control group participants were instructed regularly. Participants’ pre-test, post-test, and delayed post-test writing were analysed for overall level, coordinate level, subordinate level, and phrasal level syntactical complexity with the automatic L2 syntactical complexity analyser. Mixed ANOVA results revealed that collaborative writing interventions manifested positive effects on Chinese EFL learners' syntactic complexity development. Positive effects of task complexity were also observed. Theoretical and pedagogical implications were discussed.