It's dangerous to want to get away from earth awhile, to get your feet entirely off the ground.

想要逃离地面一会，让自己的双脚同时离开地面很危险。

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Worse still,after about 20 minutes after the ship takes off, all radio contact between ship and earth will be destroyed.

更坏的是，当飞船起飞20分钟后，所有飞船与地球的无线电通讯都被切断。

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If you escape the pull of gravity, your spaceship will be off, won't be orbiting the Earth.

如果你完全脱离重力,太空船早就飞得没影了,而不是在轨道上运行

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