值班人员要熟悉机房设备原理，遵守机房安全管理制度、通信纪律及保密制度。
参考答案：对
—It is said that Mike fought with Tom in class.
—It ______ be him. It is not ______ him to have done it like that. [ ]
A. can't; like
B. may not; as
C. can't; as
D. mustn't; like
肺泡Ⅱ型上皮细胞分泌（）
A.肺泡表面活性物质
B.肺泡表面液体薄层
C.肺泡上皮细胞
D.间质
E.毛细血管基膜和内皮细胞
