电动机电路中熔断器和热继电器各有什么作用
参考答案：在电动机电路中熔断器的作用是起短路保护，而热继电器的作用是起过载保护。
The students spent as much time getting trained as they () studying.
A. disliked
B. were
C. had
D. did
（）是一项教育工作，是有区别的为读者服务的有效方式。
