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1. If Nick weren't lazy, he wouldn't be punished.
2. If I knew the answer, I could tell you.
3. If today were Sunday, the pupils could go swimming.
4. If he had much time, he could visit his parents.
5. If she weren't very shy, she would enjoy parties.
6. If I weren't fat, I could get through the bathroom window. 
7. If we had central heating, the house wouldn't be rather cold.
8. If I knew his address, I could write to him.
9. If there weren't so many accidents, people couldn't drive very fast.
10. If they didn't speak very quickly, I could understand them.

1. If Nick weren't lazy, he wouldn't be punished.

2. If I knew the answer, I could tell you.

3. If Today were Sunday, the pupils could go swimming.

4. If he had much time, he could visit his parents.

5. If she were not very shy, she would enjoy parties.

6. If I were not fat, I could get through the bathroom window.

7. If we had central heating, the house would not be rather cold.

8. If I knew his address, I could write to him.

9. If people did not drive very fast, there would not be so many accidents.

10. If they did not speak very quickly, I could understand them.