Diolefins
二烯属; 二烯属烃
🗣️ 情景例句
Very! Hey, she forgot her bag!
非常！ 嘿 她忘了她的旅行包！
Goes without saying.
可想而知。
I know! smiled Lucy. They have steps, and they begin with L!
“我知道！”露茜笑着说，“它们有阶梯，并且这个单词是以L开头的！”