【推荐1】Do you hope to move to another city or a foreign country? It may be interesting. But how about moving to ______ planet? A US company now has a plan: sending people to Mars ______ 20 years.

To begin with, the company plans to send ______ people to go to Mars first. It will ______ them several months to get there. When they arrive, they will build a ______ first.

But Mars is not an easy place to ______. It's rocky, cold and has lots of sandstorms(沙尘暴). Also, there is ______ air for breath. So people would have to live in a special house. They would have to ______ special clothes if they go out.

People will have to find ______ resources(资源), iron, water and so on. All these could help people live there...

Sounds interesting? You might want to go to Mars now. ______ will things go well like the company hopes? We'll wait and see.

【推荐2】Long long ago, people _______ know much about the sun or the earth. They thought that the sun went round the earth. In _______ places, people even said the sun was a god. They thought that the god _______ across the sky every day on a golden horse.

Now _______ the help of scientists, we know that the earth _______ round the sun. It takes the earth a year to go all the way round the _______. Today men know how far it is _______ the earth to the sun. The sun is a star. It _______ much bigger than the earth. It looks smaller only _______ it is too far away. It is too hot for us to reach. Scientists ________ told us that the earth travels a thousand miles on its way round the sun.