basic schist

例句：

1. 1.The basic schist is a sedimentary rock that is used in construction.
   基本石炭岩是一种用于建筑的沉积岩。
2. 2.The basic schist is a very useful material for making tools and weapons.
   基本石炭岩是一种非常有用的材料，用于制作工具和武器。
3. 3. The basic schist is mined from the earth's crust, which is then processed into various products.
   基本石炭岩是从地球地壳中开采出来的，然后经过加工制成各种产品。