1.     Scientists wanted to know more about the moon. They thought the best way was to send men to the moon. The moon is about 384, 000 kilometres away from the earth. A plane can not fly to the moon because the air reaches only 240kilometres away from the earth. But something can fly even when there is no air. That's a rocket(火箭).

    How does a rocket fly? There is gas(气体) in the rocket. When the gas inside the rocket got hot enough, it will rush out of the end of the rocket. So it can make the rocket fly up into the sky.     

    Rockets can fly far out into space. Rockets with men have been to the moon. Several rockets with men have flown to another planet much farther away than the moon. One day rockets may be able to go to any place in space.

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    The moon is about 384, 000 kilometres away from us. It is so far that a plane  it. Scientists wanted to reach the moon and  about it. But how could they get there? They thought hard and at last they found a  could get there.

    A rocket can fly because of the  in it. When the gas in it got , it will rush out of the end of the rocket and make the rocket . So it can get into space. Now rockets with men  the moon. We believe that one day rockets may  in space.