锯齿形

例句：

1. 1. The car's dashboard has a serrated edge that makes it easy to grip.
   汽车的仪表盘有一个锯齿边缘，这使得握持起来非常方便。
2. 2. The old clock had a toothed wheel that was difficult to turn.
   旧时钟有一个带锯齿的轮子，很难转动。
3. 3. The knife blade is serrated, making it sharp and durable.
   刀锋是锯齿状的，这使得它既锋利又耐用。