单选题 He ______ with Smith at least four times in the past three years.
A. has been seen to meet B. was seen to meet
C. had been seen meeting D. is seen meeting

【正确答案】 A

【答案解析】[解析] 当see为被动语态形式时，其后的不定式要加to。在由until(till，up to)now，up to the present， so far， in(for，over， during)the past(last，recent)few(several，two)months(days)等构成的短语作状语的句子中也常用现在完成时。