3.1.
1) leave
2) Unless; will be
3) won't; unless
4) If we don't leave; will miss;
3.2.
2) If Gran had got a dog, she won't be lonely.
3) If you was good at football, you will play in the school team.
4) If Ben was not so stupid, he won't spend all his money on expensive clothes.
5) If Davina told truth, people will listen to her.