$\text{2. Because the car was so beautiful, I wanted to buy it.}$
$\text{3. The table which I bought is expensive. (relative clause là mệnh đề quan hệ)}$
$\text{4. If I had Tom's number, I would call him.}$
$\text{5. The girl whom you are talking to is very intelligent.}$
$\text{6. Although she is not well, she goes to school.}$
$\text{7. If we had an umbrella, we wouldn't be wet.}$
$\text{8. If the air were pure, we would be healthy.}$
$\text{9. Even though we tried to invite him to the party, he didn't come.}$
$\text{10. The teacher suggest taking part in social activities.}$
$\text{11. Although the room is very small, it's quite comfortable.}$
$\text{12. Shall we go to the movie tonight?}$
$\text{13. She wishes her son could swim well.}$
$\text{14. Rice is grown in tropical countries. (passive voice là câu bị động)}$
$\text{15. Neil Armstrong, who first walked on the moon, lives in the USA.}$
$\text{16. I suggest taking the train.}$
$\text{17. It was a beautiful day so we decided to go out.}$
$\text{18. Nam asked me if I knew his brother.}$