Duopage
双面复制页, 两面干印复制本
🗣️ 情景例句
That's fine. Thank you.
很好。谢谢你。
Good guy
好家伙
It was from the study of these that so much was learnt about the interior of the earth.
正是从这两种波的研究中，我们可以了解到地球内部的许多情况。