运行给水泵转备用时,应()。
A.先停泵后关出口阀;
B.先关出口阀后停泵;
C.先关出口阀后停泵再开出口阀;
D.先停泵后关出口阀再开出口阀。
参考答案:C
—A medical team was sent to Japan by air five hours ago.
—So they ______________ have arrived by now. The flight usually takes four hours or so.
A.might
B.could
C.must
D.need
一般检修动火,动火时间一次都不得超过()天,特殊情况可适当延长,隔日动火的,申请部门一定要复查。
A.2
B.3
C.1
D.复查