piston ring pin

例句：

1. 1. The piston ring is essential for preventing the engine from overheating.
   活塞环对于防止发动机过热至关重要。
2. 2.The pins are used to hold the parts together in the engine.
   销子用来固定发动机中的部件。
3. 3. The piston ring needs to be replaced regularly to maintain the engine's performance.
   活塞环需要定期更换以保持发动机的性能。