secondary planet pinion

例句：

1. 1.The secondary planet pinion is responsible forthe rotation of the planet's axis.
   次要行星齿轮负责行星轴的旋转。
2. 2. Inthe design of spacecraft, the secondaryplanet pinion plays a crucial role inmaintaining stability.
   在航天器的设计中，次要行星齿轮在保持稳定性方面起着至关重要的作用。
3. 3. The secondary planet pinion is essentialfor the smooth operation of the spacecraft's propulsion system.
   次要行星齿轮对于航天器推进系统的平稳运行至关重要。