For more than a century, researchers have known the basics of how limestone caves form: a tiny fracture opens in the rock, perhaps due to some internal stress, and water begins percolating through it.

超过一个世纪以来，研究者就懂得石灰岩洞形成的基本原理：可能由于内部的压力，石头上出现了微小的裂缝，然后水开始渗透。

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For more than a century researchers have known the basics of how limestone caves form: a tiny fracture opens in the rock perhaps due to some internal stress and water begins percolating through it.

超过一个世纪以来，研究者就懂得石灰岩洞形成的基本原理：可能由于内部的压力，石头上出现了微小的裂缝，然后水开始渗透。

youdao