I am so glad to see you back in Beijing and how long _______ in New York.

问题描述:

I am so glad to see you back in Beijing and how long _______ in New York.
A.have you stayed B.did you stay C.do you stay D.will you stay
为什么呢

如果是B答案,就表示问的是过去的一个事实,即住了多久.