casing round thread

例句：

1. 1. Theengineer used a casing to protectthe delicate electronics inside.
   工程师用一个外壳来保护里面的精密电子设备。
2. 2. The car's engine is housed in acasing that looks like a traditionalJapanese kimono.
   汽车的发动机被安置在一个看起来像传统日本和服的外壳中。
3. 3. The scientist used a casing to contain the fragile samples inside.
   科学家用一个外壳来容纳里面的脆弱样本。