@nguyenngoclananhpt

1. If we don't pollute the environment, we won't have any diseases

2. If I were you, I would get in touch with your relatives as soon as possible 

3. If I spoke English well enough, I would work in that foreigner-invested company

4. If people didn't hunt whales, sperm whale populations wouldn't be at risk. 

hoặc: If people hunt Sperm whale populations, they will be extincted

5. All those toys ought to be put away before dinner

6. If I were you, I wouldn't buy that house

7. It's interesting to learn how the dolpins communicate with each other 

8. Although people can learn the basic skills very quickly, they are afraid of using computers

hoặc : Although people are afraid of using computers, they can learn the basic skills very quickly