Read 1a and answer the questions.
1. Have the scientists found life on other planets? No. 
2. How many planets go around the sun? Eight.
3. What’s called the solar system? The sun and its planets are called the solar system.
4. Some spaceships have gone beyond the solar system, haven’t they? Yes.
5. Do you think there are lives on other planets in space?

Our Earth
Do you want to know about the earth? Now, let me tell you something about it.
The earth is the third planet from the sun in our solar system and is named after old English. It goes around the sun. The moon is its only natural satellite. Its diameter is 12,742 kilometers. The surface area of the earth is 510 million square kilometers and the temperature is between - 89.2°C and 61°C. The air has 21% oxygen. So plants, all kinds of animals and human beings can live on the earth.
The population of the world has reached 6.8 billion. Do you want to make friends with us?