| Tense of English verbs, as an important category in English grammar, is also one ofthe oldest subjects studied by linguists and grammarians. The traditional grammarians definetense as a grammatical category indicating time distinctions. The grammarians hold that tenseis used to indicate time and there is a one-to-one correspondence between tense and time: thepresent tense usually indicates present events, while simple past tense indicates past events.However, this view has been challenged by many language facts. The simple past tense canrefer not only to events or states that took place or existed in the past, but also to or forcounterfactual events or politeness. Since the different uses are connected with the simple pastform, we may consider it as a polysemic category.In the present thesis, the author analyzes the polysemy phenomenon from the perspectiveof cognitive linguistics, or more specifically, from the perspective of prototype theory.According to the prototype theory, categories are structured around a prototype. The presenceor absence of enough family resemblance decides the membership of an entity to a category.The author analyzes the state use, habitual use, counterfactual use and pragmatic softener useof the simple past tense, and points out that all the uses of the simple past tense do share somefamily resemblance: the distance of time relation. It is a kind of objective temporalrelationship in the state use and habitual use, that is to say, simple past tense is the timerelation of priority, simultaneity and posteriori between an action state and its reference time.This is the prototype of the simple past tense. In its use of counter factuality and pragmaticsoftener, the kind of relationship is subjective time relation of distance, which is thenon-prototype of the category.The extension of the simple past tense category from its prototype use to thenon-prototype uses is also discussed in the thesis. The author holds that the main mechanismof the extension is metaphor. Or rather, the objective time relation of distance indicated by thesimple past tense is mapped onto the subjective relations through metaphorical extension. |
