Question

what are relative clauses and give three examples

Answer 1

Relative clauses are clauses starting with the relative pronouns who*, that, which, whose, where, when. They are most often used to define or identify the noun that precedes them
I bought a new car. It is very fast.
→ I bought a new car that is very fast.

She lives in New York. She likes living in New York.
→ She lives in New York, which she likes.

Answer 2

A defining relative clause usually comes immediately after the noun it describes.

For example
1. Children who hate chocolate are uncommon.
2. They live in a house whose roof is full of holes.
3. An elephant is an animal that lives in hot countries.