mill teeth

例句：

1. 1. The machine is used to grind the teeth of the gears.
   这台机器用于磨削齿轮的牙齿。
2. 2.The mill teeth are essential for grinding metal parts.
   磨齿机对于磨削金属零件至关重要。
3. 3. The mill teeth were designed to be very precise and efficient.
   磨齿机的设计非常精确和高效。