首字母填空，根据短文内容及首字母提示，填写所缺单词.

    It seems to us that Earth stands quite stable (稳定的). But it is really m____ all the time. It turns around a make-believe line through its centre. We c____ this make-believe line Earth's axis(轴). The t____ ends（尽头） of Earth's axis are its poles(极). It t____ Earth 24 hours to travel around its axis once. We look at the sun and say it ‘rises’ and t____ across the sky, but the sun doesn't really do so. It is the turning of E____ that makes us feel that the sun were moving across the sky. We can't see the Earth is moving b____ everything on Earth is turning around it.

    As Earth moves around every 24 hours, the first half of Earth faces the sun and then the other h____. When our half of Earth is f____ the sun, we say it is day. When our half is a____ from the sun, we say it is night. It is the turning of Earth that tells us when to get up and when to go to bed.