Ответ:

ex 1

1) are you doing

2) have just finished

3) haven't done

4) had given

5) look

6) can't

7) have

8) won

9) couldn't

10) has played

ex 2

1) some

2) in front of

3) carefully

4) weren't

5) best

ex 3

1) yet

2) will send

3) was working

4) should

5) best