A-A+
He must be in the building because he was seen
问题详情
He must be in the building because he was seen ______ the building just now.
A．entering
B．enter
C．to enter
D．having entered请帮忙给出正确答案和分析，谢谢！
参考答案
正确答案：C
解析：本题考查非谓语动词不定式的用法。表示感官的一些动词如：see，hear，watch， notice等后面需接不带to的动词不定式做宾语补足语，与宾语一起构成复合宾语。但在这些词用作被动结构时，省去的to需加上，不定式做主语补足语。如：The workers are made to work from day to night.
