vocabulary

1. A large round thing in space that moves around the sun is called planet.

2. A light-year is the distance which light travels in one year.

3. The Milky Way, our galaxy, has roughly thirty billion stars like our sun.

4. More than hundreds of volcanoes still erupt today. These are called active volcanoes.

5. The Antarctica is actually a cold desert that is the only continent on the earth without river or a lake.

6. When the earth's shadow falls on the moon, this event is called an eclipse.

7. The degree of heat or cold in a body, room, country is called temperature.  

8. It is a hard stone that is like a clear glass and is expensive. Most of them come from Africa. They are diamonds.

9. Finding enough meat was a big problem for primitive man.

10. Earthworms dig tunnels that make it easy for air and water to reach the roots of the plants.

11. A person who studies or knows a lot about the sun, the moon and the stars, is called astronomer.

12. Earthworms drag dead leaves, grass and flowers into their burrows. When this plant material decays, it makes the soil more fertile.

13. It is soft white thing that falls from the sky when it is very cold. It is not rain. It is snow.

14. A long round tool that is used to see the stars, the moon and space is called telescope.

15. A violent storm which sucks up the air around houses. It is not hurricane. It is tornado.