英语翻译
P19
It seems to us that the earth stands quite still.But it is really moving all the time.It turns around a make-believe line through its center.We call this make-believe line the earth's axis .The two ends of the earth's axis are called its poles.It makes the earth twenty-four hours travel around its axis once.
We look at the sun and say it "rises" and travels across the sky,but the sun doesn't really do so.It is the turning of the earth which makes us feel as if the sun were moving across the sky.We can't see that the earth is moving because everything else on the earth is turning with us.As the earth turns around every twenty-four hours,first one half faces the sun and then the other half.When our half of the earth is facing the sun,we say it is day.When our half is away from the sun,we say it is night.It is the turning of the earth that tells us when to go to bed and when to get up.
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