51. They planned to go to Beijing for sightseeing but because of their daughter’s unexpec

问题补充：

51. They planned to go to Beijing for sightseeing, but because of their daughter’s unexpected illness they had to stay at home .

A. instead

B. really

C. however

D. Though

答案：

(答案→)A. instead

B. really

C. however

D. Though

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