反应温度主要观察（）
A、提升管底
B、提升管中
C、沉降器温度
D、提升管出口
参考答案：D
Class, please stand ______. [ ]
A. down
B. up
C. to
D. in
It is hard for people in the country to believe that the minister could survive in such ________ weather conditions.
A．severe
B．obvious
C．positive
D．sceptical
