Abstract The developmental patterns that learners follow as their language develops in syntactic complexity has gained much attention in L2 writing research recently. This study aims to contribute to the growing body of empirical literature testing the hypothesis that learners move through a set of stages in their use of complex structures for L1 Turkish learners of L2 English (Biber et al., 2011). It also aims to contribute to the limited literature on the within-genre topic effect on syntactic complexity. Complexity developmental stages of 90 intermediate level L1 Turkish learners were examined in their argumentative essays on three different topics (cell phones, online learning, and death penalty). Our findings showed that learners were developmentally in Stage 2 and Stage 3, with frequent use of finite adverbial clauses, attribute adjectives embedded in the noun phrase, and prepositional phrases as adverbials within the clause, which is in line with their proficiency level. Thus, our findings conform to the hypothesized stages of complexity development. Our findings also illustrated a significant effect of the death penalty topic on learners' complexity developmental stages, which is probably due to its greater cognitive demands as a more impersonal topic than the others.

中文翻译：

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二语学习者议论文写作的句法复杂性：发展阶段和体裁内主题效应

摘要 学习者随着语言在句法复杂度上的发展所遵循的发展模式最近在二语写作研究中得到了广泛关注。本研究旨在为越来越多的实证文献做出贡献，以检验以下假设：学习者在使用复杂结构的过程中为 L2 英语的 L1 土耳其语学习者经历了一系列阶段（Biber 等，2011）。它还旨在为关于句法复杂性的类型内主题影响的有限文献做出贡献。在他们关于三个不同主题（手机、在线学习和死刑）的议论文中，研究了 90 名中级 L1 土耳其语学习者的复杂性发展阶段。我们的研究结果表明，学习者在发展阶段处于第 2 阶段和第 3 阶段，经常使用有限状语从句，定性形容词嵌入名词短语，介词短语作为副词在从句中，符合他们的熟练程度。因此，我们的发现符合复杂性发展的假设阶段。我们的研究结果还说明了死刑主题对学习者复杂性发展阶段的显着影响，这可能是由于它作为一个比其他主题更客观的主题具有更高的认知需求。