alunite expansion agent for concrete

例句：

1. 1. Theconstruction site was littered with large blocksof limestone.
   施工现场到处都是大块的石灰石。
2. 2. The white marble statue is a masterpiece of ancient Greek art.
   这座白色大理石雕像是古希腊艺术的杰作。
3. 3. The builders used limestone to build the wallsof the new house.
   建筑工人用石灰石建造了新房子的墙壁。