i hear he will come in_ a .a day or two b.one day or two c.one and two days d.one day or two days为什么不选b?

问题描述:

i hear he will come in_ a .a day or two b.one day or two c.one and two days d.one day or two days
为什么不选b?

固定词组
in a day or two.没有为什么