为了保证达到与生产线速度高度一致，有些生产线在层压机的上复合辊装上（）。
参考答案：直流电机
.You can have _________ second try if you fail______ driving test this time.
A．the; a
B．the; the
C．a; the
D．a;/
―Congratulations, Jane, you have won the first prize in the physics competition.
―Thank you, Mr Green. I can’t make such great __________ without your help.
A．experience
B．experiment
C．progress
D．operation
