天然气场所最好应使用（）电源开关和灯具。
A、普通型
B、防爆型
C、直流型
D、隔离型
参考答案：B
The police ________ the lost child and tried to find his parents.[ ]
A. took up
B. took in
C. took over
D. took after
扑救木质楼板、吊顶的建筑物火灾时，应当射水探试楼板、吊顶强度，确认没有塌落危险后，应保持前虚后实探步前进的方式进入室内救人、灭火。
