--I’m going to the States?--How long you in the States?A. are; stayed　　 B. are; staying　　

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，短暂性动词的进行时表示将要做什么，由第一句be going to表示将要去，be staying表示将要住多长时间，句子意思“你将在美国住多长时间？”，A表示被动；C表示现在完成式；D表示一般过去式，所以选B