I saw Tom into the classroom without .
A. slide; found
B. sliding; find
C. sliding; being found
D. to slide; being found
网友回答
A. slide; found
B. sliding; find
(答案→)C. sliding; being found
D. to slide; being found
解析：考查动词的复合结构和介词后动词的被动语态。句意：我看到Tom 溜进了教室而且没有被发现。第一空：现在进行时做宾补表示动作正在进行。介词后的被动语态应为being done的形式。