1. Prince Charles is heir to the throne of England . His wife was Princess Diana.

➜ Prince Charles who is heir to the throne of England whose wife was Princess Diana.

2.Microsoft has a lot of power in the computers . That annoys some people .

➜Microsoft which annoys some people has a lot of power in the computers

3. The Euro replaced a number of national currencies . It was introduced in January 2002 .

➜The Euro who was introduced in January 2002 replaced a number of national currencies.

4. Friend ran for ten year . It is on of my favorite series .

➜Friend which is on of my favorite series ran for ten year

5. Venus is a very hot place . It is much closer to the Sun than the Earth is.

➜Venus which is much closer to the Sun than the Earth, is a very hot place.

6. Parts of Buckingham Palace are open to the public . It is where the queen lives .

➜Parts of Buckingham Palace are open to the public where the queen lives .

7. Parts of Buckingham Palace are open to the public . It is where the queen lives .

➜Parts of Buckingham Palace are open to the public where the queen lives .

8. The greyhound is the fastest dog. It can reach speeds of over 65 kilometres per hour.

➜The greyhound which can reach speeds of over 65 kilometres per hour is the fastest dog

9. 1984 was writen by George Orwell. His real name was Eric Blair.

➜ 1984 was writen by George Orwell whose real name was Eric Blair.
10. This is Mr. Smith. His son Bill plays in our team.
➜ This is Mr. Smith, whose son Bill plays in our team.
11. Her book which became a best seller was published last year.
➜ Her book, which became a best-seller was published last year.
12. This is the bank which we borrowed the money from.
➜ This is the bank, where We borrowed the money from
13. I told you about a person who is at the door.
➜ I told you about a person, who is at the door.
14. Jack whose car had broken down had to take a bus.
➜ Jack whose car had broken down had to take a bus.