Diadduct
二[基團]加成物, 二元加成物
??? 情景例句
It is too expensive. How about half the price?
太貴了，半價怎么樣？
You think I was born yesterday!
我沒那么笨！又不是三歲小孩。
Good afternoon, class! Who's on duty today?
同學們，下午好！今天誰值日？