Decide vt. 决定；解决；判决 vi. 决定，下决心
decide on 决定；选定
decide for 作对…有利的决定；赞成做某事
decide to do 决定做某事
decide upon vt. 考虑后决定；对…作出决定
decide against 决定不；作出不利于…的判决
decide to do sth. 决定做某事，例如：
1.He decides to go to Hong Kang on vacation.
2.He decided not to call his mum.
3.I decide not to go swimming this weekend because I have a lot of homework to do.
4.When the weather began not to rain, I decided to go home.
5. I decided to go home this weekend.
6.Be sure that you decide on your colors well in advance.
7.When you decide to do some things, stick to it.
8. If you decide to do you own make-up, here are a few valuable tips that will help you look your best.
9. I have decided to work hard for our company.
10. I have decided on working hard for our company.
11. They decide to have a trip.
12. She was still young, he said, and that would be taken into account when deciding her sentence.
13. What happens next could decide their destiny.
14. The election will decide if either party controls both houses of Congress.
15. He decided Franklin must be suffering from a bad cold.