Since или for. Урок английского языка

1. We have received no news sincefor 5:30 pm.

2. Jane hasn't been to America sincefor 1981.

3. You haven't smoked sincefor two months.

4. We've been friends with Fred sincefor decades.

5. They have been ill 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. He worked at that company sincefor ten years before he retired.

10. They've been teaching here sincefor quite a long time.