1. If there weren't industrial factories inside the city, pollution could be reduced.
2. Everything on the earth wouldn't grow well if the sun didn't shine.
3. If there weren't a grammar error in this English composition, it could get a full mark.
4. If I had a typewriter. I could type it myself.
5. If I buy a new hat, I’ll give it to you.
6. If you ask the teacher, he’ll explain the lesson to you.
7. If Mary saw the sight, she could tell you about that.
8. If I knew his address, I could give it to you.
9. He would have looked a lot better if he had shaved more often.
10. If she hadn't been ill, she would have gone to work.
11. If it hadn't been raining all morning, we would have gone out.
12. If he hadn't been tired, he wouldn't have made a mistake.
13. If Peter had written to me, I would have written to him.
14. If you had asked Alice, she would have told you the truth.
15. City life would be enjoyable if everything weren't expensive.