金属的局部腐蚀比（）危害更大。 ["A.点状腐蚀","B.全面腐蚀","C.局部结垢","D.全面结垢"]
微型计算机中常用的CD－ROM是（）。 ["只读型大容量软盘","只读型光盘","只读型硬盘","半导体只读存储器"]
家犬遇到陌生人，开始会发出“哼一”的音喉鸣，进而提上唇露犬齿，陌生人再不止步，它就会发起攻击。这种行为属于（） ["防御行为","攻击行为","捕食行为","逃逸"]
A knocking sound from one cylinder of an operating air compressor indicates （）. ["a defective or broken high pressure un-loader","a loose valve plate","excessive overload","no compressio"]
LKJ在非本务状态需要退出时须进入（）即可退出。
枢纽变电所和一般变电所有哪些区别？
