Unless your friend (to have) an invitation, he (not to be able to) go to the party.
She (to be) late for the lesson if she (not to) leave earlier.
If you (to be) angry, they (not to) let you in the house.
He (not to) open the book unless he (to know)what tasks to do.
We (to have to) stay home if the weather (to get) worse.
Unless you (to be)more careful with the knife, you (to cut) yourself.
If I (to tell) you a secret, you / to promiseto keep it?
If my mother (not to have to) work next weekend, we (to be able to)go to the funfair.