I’m so glad to see you back, Lucy. How long at your grandma’s?
A. had you stayed
B. did you stay
C. have you stayed
D. would you stay
网友回答
A. had you stayed
(答案→)B. did you stay
C. have you stayed
D. would you stay
解析：考查时态。根据句意可知已经回来，故用一般过去时态。句意：很高兴看到你回来了，你再你爷爷家呆多长时间？