本章主要介绍了一些有关百科全书和物种灭绝的单词，比如，encyclopaedia, encyclopaedic, reference, alphabetical, volume, specialty, on the verge of, endangered, extinct, skeletons等等。

This episode covers the vocabulary about encyclopaedia and extinct species, like, encyclopaedia, encyclopaedic, reference, alphabetical, volume, specialty, on the verge of, endangered, extinct, skeletons and etc.