Defining ralative clauses: Children like to eat ice-cream. It can cause toothache

I. DEFINING RELATIVE CLAUSES:
1.      Children like to eat ice-cream. It can cause toothache.
2.      The woman is my mother. She understands me best.
3.      The park has a lake in it. The park is near our house.
4.      This article praises the national heroes. The history books have forgotten them.
5.      What was the name of the boy? You borrowed these books from him.
6.      I’ll introduce you to the man. His support for the project is essential.
7.      The dam is nearly empty. We receive our water supply from it.
8.      The clerk doesn’t work here any more. You asked about him.
9.      I don’t like people. People lose their tempers easily.
10. It is the important matter. We are interested in it.
11. Many diseases are no longer dangerous today. People died of those diseases years ago.
12. The lady is a famous writer. You met her at the party last night.
13. The child enjoyed the chocolates. Her mother bought them from France.
14. They drank a lot of Coke. It is diet Coke.
15. The girls are performing the play. They rehearsed it yesterday.
16. The lecturer is my uncle. He gave an interesting talk on TV last night.
17. The student kept talking about the project. It was done last week.
18. The movie theater is the place. We can see films at that place.
19. This is the student. I borrowed his book.
20. John found the cat. Its leg was broken.