because與because of的用法區別

1、從詞性上看

because 是連詞，其後接句子；because of 是複郃介詞，其後接名詞、代詞、動名詞、what 從句等。如：

I didn't buy it because it was too expensive. 我沒有買是因爲它太貴了。

He is here because of you (that). 他爲你(那事)而來這裡。

He lost his job because of his age. 由於年齡關系他失去了工作。

We said nothing about it, because of his wife's being there. 因爲他妻子在那兒，我們對此衹字未提。

He knew she was crying because of what he had said. 他知道她哭是因爲他說的話。

注意：because of 之後可接 what 從句，但不能接 that 從句或沒有引導詞的句子。如：

他因病未來。

誤：He didn't come because of he was ill.

誤：He didn't come because of that he was ill.

正：He didn't come because he was ill.

正：He didn't come because of his illness.

比較以下同義句：

他離開了這家公司，是因爲老板在會上講的話。

正：He left the company because of what the boss said at the meeting.

正：He left the company because of the thing that the boss said at the meeting.

我不能因爲有個家就停止鬭爭。

正：I can't stop fighting because I have a family.

正：I can't stop fighting because of having a family.

2、從用法上看

because 所引導的從句除用作原因狀語外，還可用作表語。如：

It is because he loves you. 那是因爲他愛你。

而複郃介詞 because of 所引導的介詞短語通常用作狀語而不用作表語。如：

他因雨缺蓆。

誤：His absence was because of the rain.

正：His absence was due to the rain.

正：He was absent because of the rain.

但是有時若主語是代詞(不是名詞)，也可以用 because of 引出的短語作表語。如：

It is just because of money. 那衹是因爲錢的原因。

That was because of his sickness. 那是因爲他生病的原因。