现代汉语中的“一”有数词、名词和形容词等实词用法 ,还有副词、连词等虚词用法。由于“一”的多义性 ,“一……就……”可以表示承接、条件和假设等关系 ,这些关系又与“时态”密切相关。“一”的各类用法所表示的意义由其基本义“最小的正整数”引申而来 In modern Chinese, “a” has nouns such as nouns, nouns and adjectives, as well as adverbs and conjunctions. Due to the polysemy of “one”, “one ...... on ...” can mean the relationship of taking over, conditions and assumptions, which are closely related to “tenses.” The meanings of the various uses of “a” derive from its basic meaning “smallest positive integer”