（）是合金钢淬火时最常用的冷却剂
A.水
B.油
C.酒精
D.防冻液
参考答案：B
下列哪项不是单细胞生物（ ）
A．草履虫
B．桃树
C．衣藻
D．酵母菌
______, some people think there is something in them.
A．His ideas may sound crazy
B．As his ideas may sound crazy
C．Crazy as his ideas may sound
D．As crazy his ideas may sound
