使用井下照明和信号综合保护器能有效（）发生电气火源、火灾和电击伤人事故。
A、降低
B、增大
C、防止
参考答案：C
The boys ______ the newspaper on the ground and began to read the news and articles in it. [ ]
A. extended
B. expanded
C. spread
D. stretched
岗位说明书需要写员工的基本信息。
