porous slag

例句：

1. 1. The construction site was covered in a layer of porous slag.
   施工现场覆盖着一层多孔熔渣。
2. 2.The engineer carefully removed the porous slag to reveal the underlying structure.
   工程师小心翼翼地移除了多孔熔渣，以揭示其下的结构。
3. 3. The porous slag was used as a building material for new buildings.
   多孔熔渣被用作新建建筑的建筑材料。