提高水泥的细度，可以产生( )影响。
A．水化速度快
B．早期强度高
C．体积收缩大
D．成本提高
参考答案：A,B,C,D
Maybe if I ________ science, and not literature then, I would be able to give you more help.[ ]
A. studied
B. would study
C. had studied
D. was studying
市场定位在实施过程中应避免的错误主要包括（）。
A.定位过宽
B.定位过窄
C.定位混乱
D.定位过度
ve you more help.[ ]