皮碗清管器由压板法兰、钢架和()组成.
A.导向器、发讯器护罩、橡胶皮碗
B.导向器、橡胶皮碗
C.发讯器护罩、导向器
D.发讯器护罩
参考答案：A
临时消防应急照明灯具宜选用自备电源的应急照明灯具，自备电源的连续供电时间不应小于（）。
A.30min
B.50min
C.60min
D.100min
The students were told to _____ their English before going abroad.
A．give up
B．polish up
C．use up
D．end up
