本研究主要就通時性的觀點詳盡地分析日語移動動詞「来る」的文法化現象，並且釐清其變化的過程。過去絕大多數進行有關日語文法化的研究都是就共時性的觀點（或是限定某一時代）使用一般語言理論的架構來探討及記述語言資料，然而鮮少研究是就通時性的觀點來考察其變化的過程。所謂的文法化並非是僅就共時性的研究就能釐清的單純現象（變化），文法化乃是牽涉許多要素的複合性現象。因此，為了釐清其變化的過程，需要就時代的變遷逐一分析其語言資料。然而以往的文法化研究都是以理論為導向，欠缺基於通時性語言資料的實證考察。於是，本研究承襲Heine（2003）的論述，主要就語意淡薄化（desemanticization）的觀點詳盡地分析上代至現代的文獻資料，釐清了日語移動動詞「来る」的語意．功能變化與型態改變的過程。

This study aims to explore the grammaticalization of Japanese motion verb kuru through diachronic analysis thus to clarify the process of its grammatical changes. Despite that growing concerns have been voiced regarding the grammaticalization of Japanese, the predominant research were conducted notably via synchronic frameworks (or restricted to a specific period) using general linguistic theories, while little has been done with regard to the diachronic process of the semantic changes. Instead of a simple phenomenon that is elucidated merely by synchronic research, grammaticalization is a complicated process in which many factors interplay. Therefore, it may be defined as the result of a process that requires one to scrutinize diachronic language data carefully. Nevertheless, research in this field has been regarded as theory-oriented with insufficient evidence resulted from diachronic language data. Based on Heine's (2003) viewpoints, the author examined the detailed diachronic data in terms of desemanticization, and further clarified the process of the semantic-functional as well as morphological change of Japanese kuru.