电空位操纵，空气制动阀在制动位时的风路为（）通（）。
参考答案：调压阀管；作用管
I regret ________ that you have failed the exam, but what you should do now is not to regret ______ so much time but to seize every moment from now on.
A．to inform; wasting
B．informing; to waste
C．to inform; to waste
D．informing; wasting
下列现象属于化学变化的是（ ）
A．电灯发光
B．水结冰
C．玻璃破碎
D．菜刀生锈
