“页岩”造句

我们必须找到从页岩中采油的经济方法.
We must find economical methods for extracting oil from shale.

我们可以从页岩中提取石油.
We can extract oil from shale.

这个地区的灰岩、砂岩和页岩都是很柔软的.
The limestone, sandstone and shale of this area were soft.