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1. If the thief hadn't left his gloves at the scene, he wouldn't have been arrested.
2. If the boy had book, he could write that essay.
3. If he had learnt his lessons carefully, he could have done that exercise.
4. If you ask the teacher , he will explain the lesson to you.
5. If Jack hadn't helped me, I wouldn't have been able to move the table.
6. If his friends hadn't been late, they wouldn't have missed the train.
7. If it hadn't rained hard yesterday, we would have gone to beach.
8. Unless you had more practice, you wouldn't speak English well.
9. Unless you leave an address , we won't be able to contact you
10. If he doesn't phone me immediately, he won't get any information.
11. If we had had a map, we wouldn't have got lost.
12. If I had had an umbrella with me, I wouldn't have got wet.
13. Unless you had told me about Sue's hair, I wouldn't have noticed.
14. If only we hadn't eaten all the food.
15. I wish I had gone to university.
16. Had I gone to the party, I'd have met Melanie.
17. He regrets not watching that film.
18. If it hadn't rained hard yesterday, we would have gone to beach.
19. If she hadn't walked in the sun yesterday, she wouldn't have felt sick.
20. If he didn't speak so quickly, I could understand him.
21. If I didn't drink too much strong coffee, I could sleep.