| 1. | The earth revolves once a year around the sun .
地球一年绕太阳公转一次。 |
| 2. | The earth revolves both round the sun and on its own axis .
地球既公转又自转。 |
| 3. | The earth revolves both about the sun and on its own axis .
地球又公转又自转。 |
| 4. | The earth revolves both round the sun and on its own axis .
地球又公转又自转。 |
| 5. | In the case of the moon the rotation keeps pace exactly with the revolution .
月球的自转与公转精确地同步。 |
| 6. | The earth revolves around the sun in an ellipse with the sun at one of the foci .
地球在以太阳为焦点的椭圆上围绕太阳公转。 |
| 7. | This motion of an object in an orbit about a center is called revolution .
像这种一个物体环绕某个中心所作的轨道运动叫做公转。 |
| 8. | The earth's rotation and its motion around the sun add an appreciable frequency shift .
地球自转与地球绕日公转产生附加的频移。 |
| 9. | The earth moving around the sun gives us a baseline for measurements of objects outside the solar system .
地球绕太阳公转，为测量太阳系外的恒星距离提供了一条基线。 |
| 10. | The tilt of the earth's axis, not the shape of its orbit, is what is responsible for the seasons .
形成季节的主要因素不是地球公转轨道的形状，而是地球自转轴的倾斜。 |
