internal spur gear

例句：

1. 1. The internal spur gear is responsiblefor transmitting power from the engine tothe wheels.
   内部齿轮负责将发动机的动力传递到车轮。
2. 2. The internal spur gear was designedto improve efficiency and reduce wear.
   内部齿轮设计用于提高效率和减少磨损。
3. 3. The internal spurgear is a crucial component of the transmissionsystem.
   内部齿轮是传动系统的关键部件。