甲壳

例句：

1. 1. The crab has a hard shell that protects its soft body.
   螃蟹有一层坚硬的壳来保护它的柔软身体。
2. 2. The spider's web is made of silk and serves as a protective cover for its eggs.
   蜘蛛网是由丝制成的，作为其卵的保护覆盖物。
3. 3. The crab's shell is used to store food and protect it from predators.
   螃蟹的壳用来储存食物并保护它免受捕食者的伤害。