– I’m leaving for Beijing next week.– How long there?A. have you stayed B. are you stayin

问题补充：

– I’m leaving for Beijing next week.

– How long there?

A. have you stayed

B. are you staying

C. had you stayed

D. did you stay

答案：

A. have you stayed

(答案→)B. are you staying

C. had you stayed

D. did you stay

解析：考查将来时表达法。本题使用现在进行时表示将来时。现在进行时代替将来时表示事先计划好，安排好的事情；而且动词是表示位置变化移动的动词。句意：—我下周去北京。—你要在那里待多久？根据句意说明是事先计划好的事情。故B正确。