1. 1. If we use less vehicles, we __will reduce__ the amount of carbon dioxide into the air.
2. 2. If you _____were___ the president, what you do to prevent air pollution.
3. 3. If there were no fresh water left, what _would happen___?
4. 4. If people (not) ___didn’t throw___ rubbish in the street, it would look better.
5. 5. if there wasn’t so much light in the cities at night, we ___would see___ the starts more clearly.
6. 6. If the water is contaminated, people ___will suffer__ from many diseases.
7. 7. If chemicals from factories are dumped into rivers and lakes, they ___will cause___ water pollution.
8. 8. If people want to protect their planet, they should _change__ their habit of using plastic bag for convenience.
9. 9. If we recycle paper, we ___will save__ 1000 trees a day.
10. 10. If people were more aware of the negative consequences of pollution, they might ___take___ actions to prevent it.

1) will reduce

2) were

3) would happen

4) didn’t throw

5) would see

6) will suffer

7) will cause

8) change

9) will save

10) take