chamotte sand

例句：

1. 1.The riverbed is covered in chammot sand.
   河床覆盖着沙砾。
2. 2. The construction crew used chammot sand to fill the gaps in the wall.
   建筑工人用沙砾填充墙壁的缝隙。
3. 3.The engineer analyzed the chammot sand for its potential use in building materials.
   工程师分析了沙砾的潜在用途，用于建筑材料。