–Glad to see you back!How long ________ you _________ in Europe?–Three months.I'm off to South
问题描述：
–Glad to see you back!How long ________ you _________ in Europe?–Three months.I'm off to South
后面是Africa next week.
A.have stayed
b.did stay
答
Glad to see you back!How long (have) you (been) in Europe?Three months.I'm off to South.
补充：
我的理解是：这个对话有很明显的时间：
Glad to see you back!- 表示现在见到你回来.那么想知道你在Europe呆了多长时间?回答也很明确：三个月.所以,我觉得应该用“现在完成时态”.
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