propeller with ring guard

例句：

1. 1.The aircraft's propeller is the most critical component of its performance.
   飞机的螺旋桨是其性能最关键的部件。
2. 2.The pilot needed to make sure the propeller was properly secured before taking off.
   飞行员需要确保螺旋桨正确固定后才能起飞。
3. 3.The engineer inspected the propeller for any signs of wear and tear.
   工程师检查螺旋桨是否有磨损的迹象。