Ответ:

1st type

1. If the train is late, we will walk.
2. She will call you if she has time.
3. If it costs too much, I will buy a smaller one.
4. If the doctor can't see me I will go somewhere else.
5. If the class is full, we will find another one.
6. What will we do if the taxi doesn't come?
7. Will you phone me if there is any problem?
8. I will ask Peter if I see him tomorrow.
9. I will go next week if I can get a train ticket.
10. If I have to, I will complain to the manager.
11. If he sees me here, he will be really angry.
12. Mary will be worried if you don't come to the airport.
13. If it snows this winter, we will go skiing.
14. I will lend them some money if they ask me.
15. If you visit Oxford, you will see some interesting old buildings.

2nd type

1. If you drove more carefully, you would not have so many accidents.
2. If he got up earlier, he would get to work on time.
3. had, would be able to tell
4. would be able to, trusted
5. sold, would have
6. would be, bought
7. would be, went
8. wouldn't mind, lived
9. were, would not
10. didn't have, would give
11. would be, phoned
12. would you like, did not live
13. would you do, suddenly won
14. Would you mind, didn't give
15. had, wouldn't go

3rd type

1. would you have done, hadn't lent
2. had asked, would have got
3. would not have married, had known
4. wouldn't have hired, had known
5. had got, would not have missed
6. had been born, wouldn't have had
7. had asked, would have lent
8. had gone, would have got
9. wouldn't have gone, had known
10. would have given, hadn't broken
11. wouldn't have gone, hadn't asked
12. would have stayed, had wanted
13. wouldn't have come, had known
14. would have gone, had been able to
15. would have visited, had known