rotating flail spreader for muck

例句：

1. 1.The car's engine is rotating smoothly.
   汽车的引擎正在平稳地旋转。
2. 2.The wheel of the bicycle is rotating.
   自行车的轮子正在旋转。
3. 3.The machine's gears are rotating at a high speed.
   这台机器的齿轮正在高速旋转。