谁能告诉我 for 的用法?

for [fɔ:; fə]

conj. 因为
prep. 给,为

例句与用法:
1、We have studied English for years.
我们学英语已有好几年了。
2、They jumped for joy.
他们高兴地跳了起来。
3、Jim is going to get material for a new book.
吉姆正打算为一部新书准备材料。
4、It is for her own good.
这是为了对她自己有好处。
5、He has a great respect for his father.
他很敬佩他的父亲。
6、What can I do for you?
我能帮你什么忙吗?
7、Are you for or against?
你是赞成还是反对？
8、He shook his head, for he thought differently.
他摇摇头，因为他的想法与此不同。