for是介词，介词后面一定用带有名词属性的词，比如名词，代词（代名词），动名词（V-ing形式）或动名词短语，也就是说根据介宾短语的规则，for后面一般接动名词，可以接名词，动名词，有时候可以接句子，表示补充。

for的用法

1、Isn't that enough for you?

那对你来说不够吗？

2、I knew he worked for a security firm.

我知道他在一家保安公司工作。

3、She appears nightly on the television news, speaking for the State Department.

她作为国务院的发言人，每晚都会出现在电视新闻中。

4、If your pharmacy doesn't stock the product you want, have them order it for you.

如果药店没有你想要的药品，让他们为你订购。

5、This is the best thing you've ever done – I am so happy for you!

这是你做得最棒的一件事——我为你感到高兴！

6、John, I'm sorry for Steve, but I think you've made the right decisions.

约翰，我为史蒂夫感到难过，但是我想你的决定是正确的。

7、Many new trains have space for wheelchair users.

许多新型列车为坐轮椅者留有空间。

8、Skis are available for hire on a daily basis.

雪橇可以按天租用。

9、he knife for cutting sausage was sitting in the sink.

切香肠用的刀放在水槽里。

10、He's soon to make a speech in parliament explaining his reasons for going.

他很快要在议会发表讲话，说明他辞职的原因。