translation.en: He was kind of a little bit nervous when he was sharing it with me, but he told me that when a penguin finds a mate that they want to spend the rest of their life with, they present them with a pebble -- the perfect pebble.
translation.zh: 他分享给我这个故事的时候有点紧张，他告诉我， 当一只企鹅找到它想要相伴一生的伴侣时， 它们会送给对方一颗鹅卵石——一非常完美的鹅卵石。