Language learning is context-dependent and requires learners to employ different sets of language skills to fulfill various tasks. Yet standardized English as a foreign language assessments tend to conceptualize English proficiency as a unidimensional construct. In order to distinguish English proficiency as separate context-driven constructs, I adopted a register-based approach to investigate academic English proficiency (i.e., specific set of language skills that support academic literacy) and general English proficiency (i.e., wide range of language skills undifferentiated by context that are measured by traditional assessments) as separate predictors of overall essay quality. In the study, students completed a general English proficiency assessment and an academic language proficiency assessment, and essays were coded for academic writing features at the lexical, syntactic, and discourse levels. Beyond the contribution of academic writing features and general English proficiency, academic English proficiency emerged as a significant contributor to essay quality. Findings suggest that academic English proficiency scores more precisely identified a subset of academic language skills that is relevant to essay writing. The article concludes by discussing implications for strategic writing instruction that articulates the key expectations of academic writing used in and beyond school contexts.

语言学习是与上下文相关的，要求学习者运用不同的语言技能来完成各种任务。然而，标准化英语作为外语评估往往会将英语能力概念化为一维结构。为了将英语水平区分为独立的上下文驱动的构架，我采用了基于寄存器的方法来调查学术英语水平（即支持学术素养的特定语言技能集）和一般英语水平（即广泛的语言技能）不会因传统评估而被上下文所区分）作为整体论文质量的独立预测指标。在这项研究中，学生完成了一般英语水平评估和学术语言水平评估，论文在词汇，句法和语篇层面上都针对学术写作特征进行了编码。除了学术写作特征和一般英语水平的贡献外，学术英语水平也成为论文质量的重要贡献者。研究结果表明，学术英语水平得分更准确地确定了与论文写作相关的一部分学术语言技能。本文最后通过讨论战略写作指导的含义，阐明了在学校环境内外使用学术写作的关键期望。研究结果表明，学术英语水平得分可以更准确地识别与论文写作相关的一部分学术语言技能。本文最后通过讨论战略写作指导的含义，阐明了在学校环境内外使用学术写作的关键期望。研究结果表明，学术英语水平得分更准确地确定了与论文写作相关的一部分学术语言技能。本文最后通过讨论战略写作指导的含义，阐明了在学校环境内外使用学术写作的关键期望。