because与because of用法的相同点与不同点：相同点：词义相同，基本词义都是因为。

都可以做原因状语。不同点：because of后面只能接名词，不能接从句。because后面只能接从句，不能接名词。例句：We couldn't understand them because they were talking in Chinese.我们听不懂他们在讲些什么，因为他们说的是汉语。The party went well because everyone entered into the spirit of things.晚会很成功，因为每个人都很投入。No new power stations have been built, principally because of the cost.没有新建的发电站，主要是因为经费问题。Just because I don't complain, people think I'm satisfied.就因为我不发牢骚，大家便以为我满意了。Because of his wife being there, I said nothing about it.他的妻子在场，我便没提及这事。She was unable to attend because of the pressures of work.由于工作紧张她不能出席。The woolly shrank because it was washed badly.毛衣因为洗涤的方法不好而缩水。I can’t get to sleep because of the noise outside.由于外面声音嘈杂我睡不着。because不能与so连用汉语习惯上说“因为…所以…”，但英语习惯上却不能将 so与because 连用。根本原因是because和so都是连词，连词只能引导从句，不能用在主句前。正：Because it was raining, we stayed at home. / It was raining, so we stayed at home.误：Because it was raining, so we stayed at home.because从句与 because of短语的转换He can’t come because he is ill. / He can’t come because of his illness.他因病不能来。辨析because与because of虽然简单，但很重要，因为掌握好类似涉及到引导从句的单词和词组在遇到长难句时，会迅速地简化问题。类似情况还有in case和 in case of，请特别注意。

1、从词性上看

because 是连词，其后接句子;because of 是复合介词，其后接名词、代词、动名词、what 从句等。如：

I didn't buy it because it was too expensive. 我没有买是因为它太贵了。

He is here because of you (that). 他为你(那事)而来这里。

He lost his job because of his age. 由于年龄关系他失去了工作。

We said nothing about it, because of his wife's being there. 因为他妻子在那儿，我们对此只字未提。

He knew she was crying because of what he had said. 他知道她哭是因为他说的话。

2、从用法上看

because 所引导的从句除用作原因状语外，还可用作表语。如：

It is because he loves you. 那是因为他爱你。

而复合介词 because of 所引导的介词短语通常用作状语而不用作表语。