swallow hole

The heavy rain caused a swallow hole to open in the meadow.

大雨导致草地上出现了一个石灰坑。

Hikers must be cautious near swallow holes, as the ground may collapse.

徒步旅行者在石灰坑附近必须小心，因为地面可能会塌陷。

Over centuries, water erosion created a deep swallow hole in the limestone plateau.

几个世纪以来，水蚀作用在石灰岩高原上形成了一个深石灰坑。