糖化室温度不低于（）摄氏度。
A.18
B.20
C.22
D.25
参考答案：D
As always when she sang in the bathroom, she________the high notes in a special way.
A．span out
B．belted out
C．spread out
D．stretch out
什么是矿井“信、集、闭”系统？
