semi-silica fireclay brick

例句：

1. 1. The bricks are made froma mixture of clay and sand.
   这些砖是用泥土和沙子混合制成的。
2. 2. The brickwalls were built to protect the structure fromthe elements.
   砖墙被建造来保护结构免受自然因素的影响。
3. 3. The bricklayers werebusy laying down the new brickwork.
   砌砖工们忙于铺设新的砖块。