ctene

例句：

1. 1. The ancient city was buried under a layer of clay.
   这个古老的城市被一层黏土所覆盖。
2. 2. The engineer used clay to make the foundation stronger.
   工程师使用黏土来使地基更坚固。
3. 3. The clay layers in the region are rich in minerals.
   该地区的黏土层富含矿物质。