because一般引導什么從句

　　例句：

　　I do it because I like it.

　　我做這件事是因為我喜歡。

　　You can trust those products because the quality never varies.

　　你可以信賴那些產品，因為它們的質量從來不變。

　　We went by bus because it was cheaper.

　　我們乘公交汽車去，因為這樣便宜一些。