Supply the correct tenses and form of the verbs in parentheses

Ex5. Supply the correct tenses and form of the verbs in parentheses:
1. The contracts signed by the company (have) _________________ been voided because
some stipulations were not met.
2. Ten miles (be) _________________ a very long distance for us to walk.
3. Each package that is not properly wrapped (have) _________________ to be returned
to the sender.
4. The keys of the house (have) _________________ been lost.
5. The plan as well as the proposals (be) _________________ to be presented in the coming
Monday meeting.
6. The box of ribbons for the electric typewriter (have) _________________ been
misplaced.
7. It is disconcerting to believe that every possible candidate (have) _________________
been rejected for one reason or another.
8. There (have) _________________ been more excitement in this city about a sporting
event.
9. To me, Mathematics (be) _________________ something very easy to master.
10. If nobody (have) _________________ bought that car from the dealer, then you should
return and make another offer.