计算机辅助工艺规程设计按其工作原理可分为（）三大类型。
参考答案：派生式，生成式及知识基系统
There are _______ unusual series of facts that everyone wants to ________all of them.
A．such many; settle down
B．such much; settle down
C．so many; set down
D．so much; set down
液压马达传动系统中，关闭主电机的信号是（）（ALARM）信号
