crank axle

例句：

1. 1. The car's engine is running smoothly because the crankshaft is in good condition.
   汽车发动机运行平稳，因为曲轴状况良好。
2. 2.The mechanic replaced the crankshaft assembly after the engine overheated.
   在引擎过热后，机械师更换了曲轴组件。
3. 3. The old car's crankshaft was rusted and needed to be replaced.
   旧车曲轴生锈了，需要更换。