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1. My father bought a computer five years ago. It still works very well
 - The computer which.....
2. There is too much light in the city at night, so we can't see stars clearly
 - If there.....
3. They have built two new schools in our city this year.
 - Two new schools....
4. I don't have a lot of money, so I don't buy a lot of new books
 - If I.....