roll speed

例句：

1. 1. The car's engine is designed to maintain a high rolling speed.
   汽车的发动机设计成保持高速运转。
2. 2.The train's wheels are made to roll at a high speed.
   火车的轮子被制造成高速旋转。
3. 3. The machine's gears are set to operate at a low rolling speed for smoother operation.
   机器的齿轮被设置以低速运行，以便更平滑地操作。