My sister wasn't feeling well, so it was not possible for her to take part in the competition.
(wasn't able to / needn't / might have been / ought to / wouldn't / must have / can't have / must not)
2.
It's prohibited for girls to wear very short skirts in our school.
(wasn't able to / needn't / might have been / ought to / wouldn't / must have / can't have / must not)
3.
It would be a good idea for the work to be completed soon.
(wasn't able to / needn't / might have been / ought to / wouldn't / must have / can't have / must not)
4.
It's clear that they have eaten all the cake - there's none left!
(wasn't able to / needn't / might have been / ought to / wouldn't / must have / can't have / must not)
5.
It's not necessary for you to help me clear the table.
(wasn't able to / needn't / might have been / ought to / wouldn't / must have / can't have / must not)
6.
It's possible he was involved in an accident.
(wasn't able to / needn't / might have been / ought to / wouldn't / must have / can't have / must not)
7.
He refused to turn down the music, although we asked him to.
(wasn't able to / needn't / might have been / ought to / wouldn't / must have / can't have / must not)
8.
There's no way I left my wallet at home. I had it on the bus!
(wasn't able to / needn't / might have been / ought to / wouldn't / must have / can't have / must not)
