Karstification
n. [地]喀斯特(或岩溶)作用
🗣️ 情景例句
He's busy preparing for class.
他忙着准备功课。
How much does a round trip ticket to go there cost?
一张去那边的往返票要多少钱？
On the first lap, Class 3 were in front.
在跑第一圈时，3班在前边。