下列说法中正确的个数有：（1）多项式5πx2y+4xy-3是五次三项式；（2）在

I can think of many cases _______ students obviously knew a lot of English words and expressions but couldn’t write a good essay.

A．why

B．which

C．as

D．where

What do you mean by saying there are only ten tickets? There    be twelve．

A．can

B．may

C．should

D．shall

固液结合的新型白酒生产方法目前普遍采用（）。

A.串蒸法

B.综合法

C.酒精加水稀释法

D.酒精净化加水法

（）比特的密钥长度DES算法的密钥量是2⁵⁶

指纹色紫，推之滞涩，复盈缓慢，主（）

A.虚热

B.瘀热

C.痰湿

D.积滞

E.血虚