制作预应力构件金属螺旋管道时，所使用的钢带厚度不宜小于( )。
A．0.2mm
B．0.3mm
C．0.5mm
D．1.0mm
参考答案：B
The discovery of the new drug is of great significance to people ______ from H1N1.
A．suffer
B．suffered
C．suffering
D．being suffered
信息筛选常用的方法有哪些
