| 1. | The earth rotates once a day on its axis .
地球绕它的自转轴一天旋转一周。 |
| 2. | The earth rotates once every 24 hours .
地球每24小时转一周。 |
| 3. | Molecules rotate and vibrate by virtue of their heat .
分子因热效应而发生转动和振动。 |
| 4. | The carriage feeds the tool while the workpiece rotates .
当工件旋转时，拖板送进刀具。 |
| 5. | So a separate rotating aerial is used for that purpose .
为此需要用一种单独的旋转天线。 |
| 6. | Explain why the vanes rotate when they are illuminated .
试解释：叶片被照亮时为什么会旋转。 |
| 7. | The isoclinics rotate in the same sense as the polaroids .
等倾线的转向与偏振镜的转向相同。 |
| 8. | This large gear turns the small one to rotate the cylinder .
这个大齿轮带动小齿轮使滚筒旋转。 |
| 9. | Seen from the earth, the sun rotates in about 27 days .
从地球上观测，太阳的自转周期约为27天。 |
| 10. | It can be used on rotating machinery and under water .
它可以用于回转式机器，也可以在水下应用。 |
