不是负反馈调节特点的是
A．使系统的活动保持稳定
B．不可逆过程
C．反馈信息能减弱控制部分的活动
D．具有调定点
E．具有滞后现象
参考答案：B
It was ___ Li Ming had always been working hard that he was admitted to Beijing University last July.
___ the saying goes, "No pains, no gains". [ ]
A. because; As
B. as; Though
C. for; As
D. since; Where
( )是一个国家的基本通货和法定的计价结算货币。
A．本位货币 B．基础货币 C．现金货币 D．高能货币
