Ответ:
2.If he doesn't come in five minutes, we will go to the park without him.
3.When we get home, I will have a bath.
4.When I'm ready, I will tell you.
5.If you want, I will buy you a sandwich.
6.If it isn't too late, we will go for a walk.
7.If you haven't a dictionary, I will give you mine.
Задание 21.
1.don't tell
2.Don't tell
3.lock
4.never
5.always
6.don't open
Задание 22.
2.myself
3.himself
4.ourselves
5.herself
6.themselves