能降暴雨和冰雹的云是:().
A.Cb
B.Ns
C.Sc
D.As
参考答案:A
But for the leadership of our Party and our Government, we __________ these splendid results.
A.have achieved
B.shouldn’t have achieved
C.should have achieved
D.would achieve
变量按其因果关系不同,可分为()和()。