Underline the relative clauses. Tick (✔) if the relative clause can be omitted.

1. The second planet from the Sun is Venus, which is sometimes called the Earth's sister.

2. The ocean, which is the body of salt water, contains 97% of Earth's water.

3. Landforms make up the areas which include mountains, hills, plains, and plateaus.

4. One of the world's most famous Earth scientists is James Hutton, who is a British geologist.

5. Arctic Ocean ice and water make up a habitat for polar bears, whose main food is seals.