4. Unless she asks you, don't tell Ann what i said.

5. Unless we hurry, we will be late

6. Unless you don't stay up late, you will be late tomorrow morning

7. Unless you don't drive too fast, you may have an accident

8. Unless he doesn't ask me, I will tell him about the plan

9. If you stop smoking, it'll be better.

10. We can only get into the house if we have a key.

1 After the children had gone to bed, we watched television

2 She hasn't had a swim for 5 years

3 I haven't met him for 5 months

4 Tom hasn't gone to this club since 1999

5 They haven't come to this city since July 

6 Tom has learned French since 2001

7 She has played chess for 3 years

8 He hasn't smoked for 5 years

9 When I arrived at the office, Jack had left there

10 This is the first time I have visited England