目前，证券交易的主要过程主要分为以下( )步骤
A．开户
B．委托
C．成交
D．交割
E．结算
参考答案：A,B,C,D
混凝土碱一集料反应是指下述中的哪种反应（）？
A.水泥中碱性氧化物与集料中活性氧化硅之间的反应
B.水泥中Ca（OH）2与集料中活性氧化硅之间的反应
C.水泥中C3S与集料中CaCO3之间的反应
D.水泥中C3S与集料中活性氧化硅之间的反应
The boy doesn't speak _____ his sister, but his written work is very good. [ ]
A. as well as
B. so good as
C. more better than
D. more worse than
