介词短语在英语中除了起形容词和副词作用,在句子中作状语、定语、表语或补足语外,还可起名词作用,在句子中作主语、及物动词的宾语或另一介词的宾语。介词短语作主语或宾语时,其意一般指:a time(时间)a place(地点)a distance(距离)a sum(总数)等。现就介词短语作句子的主语和宾语做一粗浅的归纳。1.介词短语在句子中作主语 Prepositional phrases not only function as adjectives and adverbs in English, but also serve as adverbials, attributives, predications or complements in sentences. They can also be used as nouns, as subjects in sentences, objects of transitive verbs, or objects of another preposition. . When a prepositional phrase is used as a subject or object, the general meaning of the prepositional phrase is: a time, a place, a distance, and a sum. This is a rough summary of prepositional phrases as subject and object of sentences. 1. The prepositional phrase is the subject of the sentence