直流电动机降低电枢电压调速时，转速只能从额定转速（）。
A、往下降
B、开始反转
C、往上升
D、升高一倍
参考答案：A
When it was his turn to speak, ________ , he stood up. [ ]
A. nervously and excited
B. nervous and excitedly
C. nervously and excitedly
D. nervous and excited
发展中国家货币金融发展的特征
