Mary, along with her parents Hainan for a week and they will e back soon.
A. have been to
B. has been in
C. have been in
D. has been to
网友回答
A. have been to
(答案→)B. has been in
C. have been in
D. has been to
解析：根据语境可知此句的主语是Mary，是单数，故谓语动词也要用单数形式，故排除A和C。时间状语for a week意思是一周的时间是段时间，故谓语动词必须要用延续性，故选B。