postpodosoma

例句：

1. 1. The spider's eight legs are arranged in a neat pattern.
   蜘蛛的八条腿排成整齐的图案。
2. 2.The caterpillar has four pairs of legs before it emerges as an adult.
   幼虫在变成成虫之前有四对腿。
3. 3.The scientist observed the crab's postpodosoma and noted its unique structure.
   科学家观察了螃蟹的后足节，并注意到其独特的结构。