违背毒物使用原则的是()。
A.使用时应了解其特性
B.不准用手直接拿取毒物
C.未用完的剧毒品应倒入下水道
D.剧毒品应由专人保管
参考答案:C
Would you please keep silent The weather report () and I want to listen.
A.is broadcast
B.is being broadcast
C.has been broadcast
D.had been broadcast
赤道横穿的大洲中,面积最大的是[ ]
A.亚洲
B.南美洲
C.非洲
D.大洋洲