测井常用的奥南发电机的发动机缸数为（）。
A、单缸
B、双缸
C、三缸
D、四缸
参考答案：B
I hear the 2006 World Cup is held in Germany_____ June 9m_____July 9th.[ ]
A. on; and
B. from; to
C. between; on
D. during; to
保和丸的功效是( )
A．健脾和胃B．健脾消食C．健脾止泻D．消食和胃E．消痞化积
