Bivacancy
(在原子外殼中的)雙空位
??? 情景例句
How much are the dues?
會費多少？
To lose a freind is the greatest of all loses.
失掉朋友是一切損失中最大的損失。
I didn't realize how much this meant to you.
我不知道這個對你的意義有這么大。