1. Insects have an exoskeleton, a hard outer covering that protects their bodies.
昆虫具有外骨骼，一种坚硬的外覆层，可以保护它们的身体。
2. The exoskeleton of a crab is made up of a series of hard plates called "exites".
螃蟹的外骨骼由一系列称为“外体”的坚硬板块组成。