The interactions among cognitive, affective, and linguistic factors have received scant attention in task‐based writing research. To address this gap, this study aims to examine the relationships among task complexity, task motivation, task engagement, and syntactic complexity in second language (L2) writing. One hundred L2 learners enrolled in an English‐as‐a‐second‐language (ESL) writing course at a university in the United States performed simple and complex versions of an argumentative writing task at a 1‐week interval. After each task performance, participants completed questionnaires examining their task motivation. Task engagement was measured through time on task and length of production. The essays were analyzed using specific syntactic complexity measures. The results showed that the participants dedicated more time to the complex task and displayed higher motivation levels in two orientations (identified and intention). Furthermore, they produced fewer words when faced with a complex task. Additionally, task complexity influenced only one dimension of syntactic complexity. Finally, time on task predicted two dimensions of syntactic complexity (mean length of T‐unit and mean number of complex nominals per clause). These results emphasize the need to consider cognitive, affective, and linguistic factors in task‐based writing research. By doing so, educators can develop writing tasks that effectively engage ESL learners, enhance their motivation, and promote their linguistic growth.

中文翻译：

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探索二语写作中任务复杂性、任务动机、任务参与度和语言复杂性之间的关联

在基于任务的写作研究中，认知、情感和语言因素之间的相互作用很少受到关注。为了解决这一差距，本研究旨在探讨第二语言（L2）写作中任务复杂性、任务动机、任务参与度和句法复杂性之间的关系。一百名在美国一所大学参加英语作为第二语言 (ESL) 写作课程的二语学习者每隔 1 周执行简单和复杂版本的议论文写作任务。每次任务执行后，参与者完成调查问卷，检查他们的任务动机。任务参与度是通过任务时间和生产长度来衡量的。使用特定的句法复杂性措施对论文进行了分析。结果表明，参与者将更多的时间投入到复杂的任务中，并在两个方向（识别和意图）上表现出更高的动机水平。此外，当他们面对复杂的任务时，他们说的单词更少。此外，任务复杂性仅影响句法复杂性的一个维度。最后，任务时间预测了句法复杂性的两个维度（T 单元的平均长度和每个子句的复杂名词的平均数量）。这些结果强调了在任务型写作研究中考虑认知、情感和语言因素的必要性。通过这样做，教育工作者可以开发有效吸引 ESL 学习者、增强他们的动机并促进他们的语言发展的写作任务。