悬挂保护间隙如何操作？
参考答案：
悬挂保护间隙应先将其与接地网可靠接地，再将保护间隙挂在导线上，并使其接触良好。拆除的程序与其相反。
As the most frequently spoken language in the world, Chinese ________ in many schools in Europe.
A. is teaching B is taught C. has taught D. teaches
对于轻度和中度AECOPD患者，主要致病菌为（）。
A.铜绿假单胞菌、MRSA
B.军团菌
C.肺炎链球菌、流感嗜血杆菌、卡他莫拉菌
D.多重耐药肠杆菌
E.鲍曼不动杆菌
