上述四个常用短语均有“因为”或“由于”的含意,可全部地或部份起到介词的作用(引导状语、表语、定语),一般用作短语介词(或复合介词),因而一律不可引导从句。但它们的用法却不尽相同,归纳如下。一、because of 是由 by+cause+of 演变而来,其标准用法是:只能引导状语(并且只能有一个宾语),而不能用于系动词 be 之后,例:I came back because of the rain.由于下雨,我回来了。然而 The four common phrases mentioned above all have the meaning of “because” or “because of”, and can function in whole or in part as prepositions (leading adverbials, predicates, attributives), and are generally used as phrase prepositions (or compound prepositions). Never guide a clause. However, their usage is not the same and they are summarized as follows. First, the cause of is evolved by by+cause+of. Its standard usage is that it can only lead adverbials (and can only have one object) and cannot be used after the verb be. Example: I came back because of the Rain. I was back because of the rain. however