Comparative Study Of Chinese And German Modal Verb "can" And "dürfen" Of

Based on the previous researches, this thesis applies the basic concepts and theories ofsemantics and cognitive linguistics to a contrastive research of synonymous modalverbs between two different languages:’’keyi’’（可以）in Chinese and’’dtirfen’’ inGerman. With combination of diachronic semantic evolution investigation andsynchronic corpus analysis, it describes the detailed modal meanings of the two words.Inspired by the analysis method of the “context background theor"y by Kratzer(1978),we attempt to explain the reason why polysemous synonyms developed differentmeanings and differed in details from the “bottom meaning".Through diachronic semantic evolution investigation? we assume that the bottommeaning of “keyi”（可以）could be “to provide conditions for doing something or”making a proposition and have positive inlfuences on the development of dynamicand deontic modality; according to the previous diachronic researches on “dtirfen”and the synchronic semantic analysis in this thesis, we assume that the bottommeaning could be “to be constrained by external world" and tended to be conservative.“Dtirfen” includes three modal meanings: dynamic, deontic and epistemic modality.We also analyzes the polite usages of “ke”yi（可以）and “dtirfen” contrastively.“Keyi”（可以）can express request, dissuade and proposal politely, while “dtirfen” canonly express request of doing something conducted by the speaker. The differencesare subjected to different bottom meanings.