Abstract:English preposition consists mainly of simple preposition, compund preposition, double preposition, phrasal preposition, participle preposition and special preposition. In a sentence a prepositional phrase can serve as an attributive, an adverbial, a predicative, an object (a subject) complement, a subject and a connective. The substitute function of a prepositional phrase should be paid attention to. In addition, a prepositional phrase can be used to express the meaning of a verb in order to simplify the sentence. Moreover, we must always keep in mind the differences between a preposition and an adverb (a pronoun, an infinitive).