=>
1. This is Mrs. Jones, whose son won the championship last year.
2. Mr. Smith, whom I had come specially to see, said he was too busy to speak to me.
3. His girl friend, whom he trusted absolutely, turned out to be an enemy spy.
4. The car that we were in had bad brake.
5. This is the story of a man whose wife suddenly loses her memory.
6. The man whom I was waiting for didn't turn up.
7. The firm which I work for is sending me to New York.
8. I saw several houses, most of which were quite unsuitable.
9. The Smiths, whose house had been destroyed in the explosion, were given rooms in the hotel.
10. He wanted to come at 2 am, which didn't suit me at all.
11. She climbed to the top of the mountian to see the wonderful view which she had bene told about.
12. Lan didn't want to meet Nam, which makes him feel sad.
13. The man who answered the phone said Tom was out.
Who -> đtqh chỉ người
Whom -> đtqh chỉ người (tân ngữ)
Which -> đtqh chỉ vật/thay thế cả mệnh đề
Whose -> đtqh thay thế tính từ sở hữu
When -> đtqh chỉ thời gian
That -> đtqh chỉ người, vật
Giới từ + whom/which

4.The car had bad brakes. We were in this car.

→We were in this car which had had brakes.