—I’m going to the States.—How long you in the States?A. are; stayedB. are; staying　C. have

问题补充：

—I’m going to the States.

—How long you in the States?

A. are; stayed

B. are; staying

C. have; stayed

D. did; stay

答案：

A. are; stayed

(答案→)B. are; staying

C. have; stayed

D. did; stay

解析：考查时态：句意：--我要去美国。--你要在美国待多久。从第一句话可知用一般将来时，只有B是现在进行时表示一般将来时，选B