small coal mines

• 小煤矿

small coal mines的用法和样例：

例句

1. Medium and small coal mines in north of Shaanxi Province generally adopt longwall remaining coal pillars support mining.
   摘要长壁留煤柱支撑法开采是陕北中小煤矿普遍采用的一种采煤方法。
2. The belated enforcement of mining safety standards has led to closure of many small mines and temporary shortage of coal.
   采矿安全标准姗姗来迟后，许多小煤矿被关闭，导致了暂时性的缺煤。