A light, porous rock formed from compacted volcanic ash.

• Grain size ranges from fine sand to coarse gravel.

由固结火山灰组成的轻质多孔岩石。

• 颗粒大小可从细砂到砾石。

Nonstandard, eye-dialect spelling of tough.

• Means strong, durable, or difficult.

英语中 tough 的非标准口语式拼写。

• 表示强硬、耐用或困难。