直流电动机起动时，励磁回路断路，电动机就不能（），在运行中断路，电动机就（）。
参考答案：起动；飞转
Around the world, more and more people are _________ dangerous sports activities, because life in modern societies has become safe and boring.
A．taking out
B．taking off
C．taking part in
D．taking care of
用电单位严禁约时停送电，并不得未经申请批准而借系统停电机会自行作业。
