Abstract As an important index of working memory burden and syntactic difficulty, Dependency Distance (DD) has been fruitfully applied in the context of Second Language Acquisition (SLA) to both native and non-native language production. Recent research has focused on DD as a predictor of writing performance across different proficiencies, while the other modality of second language (L2) performance – speaking – has been largely neglected. Moreover, while previous results reported significant positive correlations between DD and writing proficiency, a lack of control for important variables such as sentence/text length may have potentially inflated the outcomes of the analyses. In this study, we examine the effects of DD across the different modalities and proficiency levels, controlling for the effects of text and sentence lengths. Results from statistical analysis show that the mean DD of L2 writing is significantly shorter than L2 speech production, indicating that L2 writing may be a cognitively more demanding task than L2 speaking. Additionally, while significant statistical differences in DD were found across proficiency levels in both L2 writing and speech, the significance disappeared after controlling for sentence and text length. The implications of the present study for future research on DD in SLA are discussed.

中文翻译：

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超越长度：研究跨L2方式和熟练水平的依存距离

摘要依赖距离（DD）作为工作记忆负担和句法难度的重要指标，已在第二语言习得（SLA）的背景下成功地应用于母语和非母语的产生。最近的研究集中在DD作为跨不同水平的写作表现的预测指标，而第二语言（L2）表现的另一种形式-口语-已被广泛忽略。此外，尽管先前的结果报告了DD与写作水平之间存在显着的正相关性，但缺乏对重要变量（如句子/文本长度）的控制可能会夸大分析结果。在这项研究中，我们检查了DD在不同方式和熟练水平上的影响，控制了文本和句子长度的影响。统计分析的结果表明，L2写作的平均DD明显短于L2语音生成，这表明L2写作比L2说话在认知上可能是一项要求更高的任务。此外，虽然在二语写作和口语能力水平上发现DD的统计学差异显着，但在控制句子和文本长度后，显着性消失了。讨论了本研究对SLA中DD的未来研究的意义。在控制句子和文本长度之后，重要性消失了。讨论了本研究对SLA中DD的未来研究的意义。在控制句子和文本长度之后，重要性消失了。讨论了本研究对SLA中DD的未来研究的意义。