1. 根据句意，选用方框内的词组填空。注意形式的变化。

add up, take part in, take action, pay for, begin with

1. （1） Last Friday we had a sports meeting. I  the basketball match.

3. （2） They said they  to protect the environment already.

5. （3） It seems unfair to make him  everything.

7. （4） Five and eleven  to sixteen. Is it right?

9. （5） First of all, I  an apology for a mistake I made last week.