1. A man answer the phone. He told me you were away.
--> A man, who told me you were away, answered the phone.
2. They volunteer to help the victims. Their houses were destroyed by a flood.
--> They volunteer to help the victims whose houses were destroyed by a flood.
3. Joan was planning to go to the conference. Her colleagues were waiting for him there.
--> Joan was planning to go to the conference, where her colleagues were waiting.
4. A waitress served us. She was very impolite and impatient
--> A waitress, who was very impolite and impatient, served us.
5. I met Alice’s father. He worked at the university.
--> I met Alice's father who worked at the university.
6. A girl was injured in the accident. She is now in hospital.
--> A girl who was injured in the accident, is now in hospital.
7. The film The Dark terrified her a lot. She watched it last night.
--> The film The Dark which she watche last night terrified her a lot.
8. A building was destroyed in the fire. It has now been rebuilt.
--> A building which was destroyed in the fire, has now been rebuilt.
9. John Bridge is one of my oldest friends. He has just gone to live in Canada.
--> John Bridge, who has just gone to live in Canada, is one of my oldest friends.
10. Don’t use this product. It is not suitable to your hair.
--> Don't use this product which is not suitable to your hair.
11. The birds have flown away. I found their nest in the tree behind my house.
--> The birds whose nest I found in the tree behind my house have flown away.
12. He is curious about the reason. She has been sad in recent days for that reason.
--> He is curious about the reason why she has been sad in recent days.
13. We enjoy traveling to Dalat. There are a lot of places of interests there.
--> We enjoy traveling to Dalat, where there are a lot of places of interests.
14. A bus goes to the air port. It runs every half an hour.
--> A bus which runs every half an hour goes to the air port.
15. You have all met Michael Wood. He is visiting us for a couple days.
--> You have all met Michael Wood, who is visiting us for a couple days.
16. We are moving to Manchester. Manchester is in the north-west.
--> We are moving to Manchester, which is in the north-west.
17. The singer had to cancel her concert. She was recovering from flu.
--> The singer, who was recovering from flu, had to cancel her concert.
18. She was greatly influenced by her father. She adored him.
--> She was greatly influenced by her father, whom she adored.
19. He isn’t looking forward to the time. He will have to leave at that time.
--> He isn't looking forward to the time that he will have to leave.
20. The biggest city in Brazil is Sao Paulo. Its population is over five million.
--> The biggest city in Brazil is Sao Paulo, whose population is over five million.