Since или for. Урок английского языка

1. You haven't smoked sincefor two months.

2. I haven't worked sincefor a mounth.

3. We've been together only sincefor a few days.

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

5. Jane has worked here sincefor two weeks already.

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

7. I haven't talked to him sincefor last week.

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

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

10. They've been in love sincefor three weeks.