一级负荷在任何情况下都不允许停电，所以应采用双电源供电或单电源双回路供电。
参考答案：错
Her________to become a teacher was held back by her poor spoken English.
A．instruction
B．situation
C．ambition
D．condition
联合循环的首要调节任务是根据（）的要求来调整机组的功率。
