This study investigates the extent to which (a) Spanish heritage (HL) and second language (L2) writers’ linguistic complexity differs across register contexts and (b) Spanish proficiency and writing motivational beliefs differentially affect HL and L2 writers’ performance. Participants were 58 HL and 54 L2 Spanish learners who completed two persuasive writing tasks—the Email to Friend and Letter to Dean tasks—designed to be topically similar while eliciting different registers. Proficiency measures included an elicited imitation task (EIT) and a cloze test. Mixed-effects models indicated that both HL and L2 writers evidenced greater lexico-syntactic complexity in the Letter to Dean task; nonetheless, HL writers demonstrated more robust cross-register distinctions in syntactic complexity. The EIT and cloze test positively predicted syntactic and lexical complexity, respectively, although differential patterns were also observed by group. Intrinsic/interest and cognitive/linguistic value beliefs about Spanish writing emerged as positive and negative predictors of linguistic complexity, respectively.

本研究调查了 (a) 西班牙传统 (HL) 和第二语言 (L2) 作家的语言复杂性在不同语域环境中的差异程度以及 (b) 西班牙语熟练程度和写作动机信念对 HL 和 L2 作家表现的不同影响程度。参与者是 58 名高级西班牙语学习者和 54 名二级西班牙语学习者，他们完成了两项有说服力的写作任务——给朋友的电子邮件和给院长的信——旨在主题相似，同时引出不同的语域。熟练程度测量包括引出模仿任务（EIT）和完形填空测试。混合效应模型表明，HL 和 L2 作家在给院长的信任务中都表现出更高的词汇句法复杂性；尽管如此，HL 编写者在句法复杂性方面表现出了更强大的跨语域区别。 EIT 和完形填空测试分别积极预测了句法和词汇复杂性，尽管按组也观察到了不同的模式。关于西班牙语写作的内在/兴趣和认知/语言价值信念分别成为语言复杂性的积极和消极预测因素。