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    Lots of scientists believe there's life on other planets．Because of this，they keep doing research about the universe．They have sent astronauts to the moon．And they have {#blank#}1{#/blank#}the answer．There's no life on the moon．Not long ago they {#blank#}2{#/blank#}spaceships to Mars．There，they didn't find life．And they found the environment of Mars was {#blank#}3{#/blank#}from that of the earth．Then they knew it was{#blank#}4{#/blank#}for people to live on Mars．

    {#blank#}5{#/blank#}they haven't received a message from other planets，they believe their idea is right．Recently they have {#blank#}6{#/blank#}a planet．It's {#blank#}7{#/blank#}Proxima Centauri．It's very {#blank#}8{#/blank#}to our earth．It is just over four light years away．Proxima Centauri is {#blank#}9{#/blank#}than the earth．And there's water on this planet．That {#blank#}10{#/blank#}mean that life is possible there．Now scientists are studying this planet．Soon they will tell people the answer．

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