Abstract Although a major line of task-based research investigates the effects of task condition, little attention has been paid to the differential effects of open vs. closed tasks on L2 learning. Some researchers claim that closed oral interactive tasks are more effective, as the predetermined solution forces learners to continue without giving up, leading to greater negotiation for meaning, language recycling, and provision/incorporation of feedback. Because there is little empirical evidence to support such claims, the present study was conducted to investigate the combined effects of task closure and task complexity on the L2 written performance of 83 Korean learners of English. Participants performed two tasks whose task complexity was operationalized as number of elements. Half of the participants carried out closed task versions, and the other half carried out open versions. Greater task complexity was found to increase cognitive load shown by learner self-ratings, expert judgments, and time-on-task measures. Regarding written performance, greater task complexity had significant effects on lexical diversity and proportion of target-like use of articles. Contrary to previous claims, open tasks were found to elicit greater lexical diversity than closed tasks.

中文翻译：

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任务关闭和任务复杂性对 L2 书写性能的影响

摘要 尽管基于任务的研究主要研究了任务条件的影响，但很少有人关注开放任务与封闭任务对二语学习的不同影响。一些研究人员声称封闭式口头互动任务更有效，因为预定的解决方案迫使学习者继续而不放弃，从而导致对意义、语言循环和提供/合并反馈的更大协商。由于几乎没有经验证据支持这种说法，因此本研究旨在调查任务结束和任务复杂性对 83 名韩国英语学习者的 L2 书面表现的综合影响。参与者执行了两项任务，其任务复杂性被操作为元素数量。一半的参与者进行了封闭任务版本，另一半进行开放版本。发现更大的任务复杂性会增加学习者自我评价、专家判断和任务时间测量所显示的认知负荷。在书面表现方面，更大的任务复杂性对词汇多样性和文章目标类使用比例有显着影响。与之前的说法相反，发现开放任务比封闭任务引起更大的词汇多样性。