I'd like to buy a book on ——Mars.A.a BI'd like to buy a book on ——Mars.A.a B.an C.the D./为什么选D?

问题描述:

I'd like to buy a book on ——Mars.A.a B
I'd like to buy a book on ——Mars.A.a B.an C.the D./为什么选D?

特殊名词