Alkene
[ ['ælki:n] ]
高中 Senior High
n. [化]烯烃,链烯
🗣️ 情景例句
But first in the school-rooms.
但首先是在教室 。
Play dumb.
装傻！
When you visit London, one of the first things you will see is Big Ben,
当你游览伦敦时，首先看到的东西之一就是“大本”钟，