earth of casing

例句：

1. 1. The engineer designed the new car with a sleek casing.
   这位工程师设计了一款外观光滑的新车。
2. 2. The scientists used a variety of materials to construct the casing.
   科学家们使用了各种材料来构建壳体。
3. 3. The box was carefully wrapped in brown paper and placed inside the casing.
   这个盒子被仔细地用棕色纸包裹起来，放在了壳体内部。