Since или for. Урок английского языка

1. You haven't smoked sincefor two months.

2. I haven't met Jill sincefor the end of the school.

3. My boss has been away sincefor half a day only.

4. I've read two books sincefor the weekend.

5. She has been in hospital sincefor Monday.

6. He hasn't played the piano sincefor he was a boy.

7. These cherry trees have bloomed every spring sincefor 1980.

8. He's been working in the field sincefor early this morning.

9. They have been raising horses and cows on their farm sincefor many years.

10. John and Bob have been working on this project sincefor five months already.