仓库的具体形式有（）。
A.库房
B.料棚
C.货场
D.集装箱
E.托盘
参考答案：A, B, C
It has been announced that all the students ____ put on masks before going to school in case they are infected with SARS virus.
A．shall
B．will
C．need
D．may
只有在局部通风机及其开关附近10m以内风流中的瓦斯浓度都不超过( )%时，方可人工开启局部通风机。
A．0.2 B．0.3C．0.5 D．0.8
