Slickensides
n. （与邻石摩擦而成之）岩石光滑面；镜岩
🗣️ 情景例句
I think your food is very tasty, too.
我想你们的饭菜也是非常可口的。
I know the boy whose father is a college president.
我知道那个男孩的父亲是大学校长。
but where had it come from?
但它是从哪儿来的呢？