This paper describes the ablauting patterns in Siyuewu Khroskyabs, an understudied Gyalrongic language. Ablaut is only found in verbs containing closed syllables, and ablaut patterns in Siyuewu preserve Proto-Khroskyabs patterns relatively well. After providing a synchronic description of verb-stem functions and ablauting patterns, implicative entropy is used to model Siyuewu’s ablauting status. Entropy measurements reveal Siyuewu to have relatively low ablaut predictability, which may be suggestive of a historically conservative ablauting system. On the basis of this quantitative analysis, the current paper proposes an internal reconstruction of ablauting patterns, and postulates a series of velarised vowels for Proto-Siyuewu. Analogical changes are identified through comparison with other Gyalrongic languages. The reconstructed verb forms and patterns are then compared with neighbouring Gyalrongic languages and the directionality of analogy is discussed.

中文翻译：

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四岳伍赫斯基的动词-词干模式的复杂性和历史

本文介绍了被广泛研究的Gyalrongic语言Siyuewu Khroskyabs中的燃烧模式。仅在包含封闭音节的动词中发现了Ablaut，而四月无语中的Ablaut模式则保留了原始Khroskyabs模式的相对较好。在提供了动词-词干功能和过失模式的同步描述之后，使用内含熵来建模四月屋过失状态。熵测表明四月五号具有相对较低的白化可预测性，这可能暗示了历史上保守的白化系统。在此定量分析的基础上，本论文提出了内部重建烧迹模式的方法，并提出了一系列原始元音雾化的元音元音。通过与其他Gyalrongic语言进行比较来识别类比变化。