Ответ:

1) never

2) have never

3) haven't gone

4) haven't finished

5) has just completed

1) has been

2) has

3) have been

4) returned

5) written

6) done

7) traveled

8) have

9) haven't lived

10) eaten

11) haven't

12) met

13) have

14) has broken

15) have entered