He slipped(溜进) into the classroom without __________

试题详情及答案解析

He slipped(溜进) into the classroom without ___________.

A．noticed	B．noticing
C．being noticed	D．was noticed

答案：C

试题分析：考查非谓语动词。句中的without为介词，且notice与主语he之间被被动关系。句意：他乘没人注意溜进了教室。故C正确。
考点：考查非谓语动词