Not for a moment sightseeing while in Europe.
A. has he stopped
B. he stops
C. did he stop
D. he did stop
网友回答
A. has he stopped
B. he stops
(答案→)C. did he stop
D. he did stop
解析：考查倒装句和时态：句意：在欧洲的时候，他一刻也没有停下看风景。Not for a moment是否定意义的词，放在句首的时候，句子用部分倒装，因为是在欧洲的时候，用一般过去式，选C。