若在厂区听到三次报警声，表明电厂进入（）。
A、应急待命
B、厂房应急
C、厂区应急
D、总体应急
参考答案：B
It was quite a serious accident, _________ caused by careless driving.
A．which I think was
B．I think which was
C．which I think it was
D．I think which it was
就我国当前基础教育课程改革现状和师资力量来看，___________是一种最佳的校本研究形式。
