怎么辨別因為是介詞還是連詞

because是介詞時后接名詞或名詞詞組，because是連詞時接一個完整的句子。如Because of the rain,the sports meeting has been put off. Because it rains,the sports meeting has been put off.

because的用法

（1）because的基本意思是“因為”，強調直接造成某種結果的理由和原因，所引導的原因狀語從句多置于主句之后，有時為了強調，也可置于主句之前，并用逗號與句子的其他部分隔開。

（2）because還可用來引導讓步狀語從句，這時，通常用于否定句或疑問句中。

（3）because有時還可引導表語從句。

because和because of的用法區別

一般句型結構為：

1.句子+because+句子

2.because+句子+句子

3.because of+名詞/代詞

從以上句型結構可以看出，Because是連詞，連接兩個句子，如：

1.I was worried because Mary was late.我很著急因為瑪麗遲到了。

2.Because I was tired,I went home.因為我很累，我回家了。

Because of是復合介詞，其后接名詞、代詞、動名詞、what從句等。如：

I was late because of the rain.我因為下雨遲到了。

Because of之后可接 what 從句，但不能接that從句或沒有引導詞的句子。如：

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

他離開了這家公司，因為老板在會上講的話。

He didn't come because of his illness.他因病沒有來。