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20. If she had studied hard, she wouldn't have failed the exam last week.
21. If the bus hadn't been so crowded, she wouldn't have had to walk to the office.
22. If he didn't get up early, he wouldn't get good health.
23. If she weren't weak, she would go out very often.
24. If the sun hadn't been in the right direction, the photographs wouldn't have come out very well.
25. If he didn't watch video film by night, he wouldn't feel asleep by day.
26. If he hadn't been too lazy, he wouldn't have failed int he examination.
27. If my car hadn't broken down, I wouldn't have missed the meeting.
28. If Susan didn't eat too much, she wouldn't be overweight.

29. If we had had enough money, we would have gone on holiday.
30. If he had hurried, he wouldn't have missed the train.

31. If today were Thursday, we could go swimming.