投资产权结构是项目投资前期研究的重要内容，通常在项目研究的( )确定。
A．初期B．中期C．后期D．中后期
参考答案：A
The visitors here are greatly impressed by the fact that_______ people from all walks of life are working hard for_____ new Binhai.
A．不填; a
B．不填;the
C．the; a
D．the; the
对电动机轴承的振动有何规定？
