Раскройте скобки, образуя условные предложения :
1. If they had remembered your address, they ... (to send) you a posteard.
2. If tom saw a car crash, he (to telephone) the police.
3. If you are not sure, what to say, you ... (to have) to guess.
4. If she ... ( not to be) very ill, she wouldn't have been absent from English.
5. If my perents had god seats, they ... (to enjoy) the play last night.