Ex.1
1. has
2. has
3. have
4. has
5. haven't
6. hasn't
7. have
8. has
9. Has
10. haven't
Ex.3
1. We have seen this film many times.
We haven't seen this film many times.
Have we seen this film many times?
2. Marry has cleaned the windows.
Marry hasn't cleaned the windows.
Has Marry cleaned the windows?
3. Our parents have known Peter since last year.
Our parents haven't known Peter since last year.
Have our parents known Peter since last year?
Ex.5
1. never
2. recently
3. yet
4. ever
5. just
6. so far
7. already
