2019年mpacc考试英语真题——介词和介词短语253

{01}---Why are you so nervous?
---To our great surprise, we found        by the strangers
A.we monitored
B.ourselves monitored
C.us to monitor
D.ourselves monitoring
解析：本题考查非谓语动词。本题考查过去分词作宾语补足语，find sb done发现某人被……，句意：让我们很吃惊的是，我们发现被监视了，选B。
本题选B。