关键词: 格形态, 功能扩张, 指称, 信息结构, 体范畴

Abstract: Based on the concept of mighty category from Linguistic Inventory Typology, this paper investigates the functional expansions of morphological cases in human languages, focusing on the following functions: 1) Noun-related functions close to case meanings, which are normally represented in nominal elements such as referentiality, information status and animacy; 2) Verbrelated functions outside of case meanings, which are normally carried in verbal elements such as tense, aspect, modality and evidentiality; 3) Non-categorical functions, which are semantically discrete functions depending on different lexical items. The powerful and diverse expansion ability of mighty categories is demonstrated by the expansion of morphological cases across languages, as in Latin, Japanese, Korean, Finnish, Qiang, Sulong, Primi and northwest Chinese. Trans-categorical expansion of case morphology is often based on the distributional constraints of the markers, resulting in the so-called parasitic categories, and sometimes it may take place on the basis of semantic-cognitive mechanism such as metonymy. The Principle of Maximal Utility of Linguistic Inventory plays a key role in trans-catagorical expansion of mighty categories.