A categorical initial Vsg (verb in singular) in Classical Arabic (‘verbal sentence’) is unique among the Semitic languages, and can therefore be postulated to be innovative in it. This paper situates this phenomenon in the larger context of the development of so-called deflected agreement (FSG agreement with a plural subject). A three-stage historical model is developed whereby stage 2 in particular saw an explosion of FSG agreement among almost all categories of plural subject nouns. It is during this phase that categorical initial Vsg is argued to have emerged. However, the origin of the characteristic Arabic deflected agreement rule is tentatively suggested to have begun not among plural nouns but among collectives, comparable phenomena in Hebrew and Syriac indicating a West Semitic origin. The three stages are to be understood as being each associated with different speech communities, which explains why each of the stages is still attested in different parts of the Arabic-speaking world today.

中文翻译：

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阿拉伯语中的偏差一致和动词单数：一个三阶段历史模型

古典阿拉伯语（“动词句子”）中的分类首字母 Vsg（单数动词）在闪米特语中是独一无二的，因此可以假设它是创新的。本文将这一现象置于所谓的偏离协议（FSG 协议与复数主体）发展的更大背景下。开发了一个三阶段的历史模型，特别是在第二阶段，几乎所有类别的复数主语名词都出现了 FSG 协议的爆炸式增长。正是在这个阶段，分类初始 Vsg 被认为已经出现。然而，阿拉伯文偏转协议规则的起源被初步认为不是在复数名词中而是在集体中开始的，希伯来语和叙利亚语中的类似现象表明其起源于西闪米特语。