蛹

例句：

1. 1. The caterpillar transforms into a butterfly during its larval stage.
   毛毛虫在其幼虫阶段会转变为蝴蝶。
2. 2. During the pupation process, the caterpillar is encased in a hardened exoskeleton.
   在蛹化过程中，毛毛虫被坚硬的外骨骼包裹。
3. 3. The transformation from caterpillar to adult is a crucial life cycle event.
   从毛毛虫到成虫的转变是一个重要的生命循环事件。