Abstract：There are many appellations about phrasal verbs. Sometimes they are called two-word verbs, compound verbs and so on. A phrasal verb in this paper is an idiom, which consists of a verb followed by a preposition (for example: stand for, call with), a verb followed by an adverb (for example: come out, hold up), or a verb followed by an adverb and a preposition (for example: go in for, look up with). If an object does not follow a phrasal verb, it is simple to know the particle，because the particle can only be the adverb in this situation. If an object follows the phrasal verb, and the phrasal verb is made up of a transitive verb and a particle, the particle must be an adverb. On the contrary, if the phrasal verb is made up of an intransitive verb and a particle, the particle must be a preposition.

Key words： analysis; particle; transitive; intransitive; phrasal verb

摘 要：短语动词有很多称呼。比如：二词动词，复合动词等。本文所讲的短语动词是指由动词和介词﹑动词和副词所组成的，其意义和功能相当于一个普通动词的短语。如果短语后面没有直接宾语，其结构很好辨认。在其后有直接宾语的情况下，这个短语动词要么是不及物动词和副词组成，要么由及物动词和介词组成。 短语动词具有整体性和习语性。其意义变化主要有三种。1: 动词和介词（副词）保持原义和字面意义。2: 动词意义有所改变，介词（副词）失去部分原义。3: 动词和介词（副词）都失去原意，而紧密结合表示一个新义。

关键词：虚词;及物动词;不及物动词;短语动词