用以衡量一国的国民产出的重要经济指标国内生产总值简称为( )。
A．GNP
B．GDP
C．PDI
D．NNP
参考答案：B
The rest of his life was devoted ___ pollution ___ more happily. [ ]
A. to prevent, to live
B. to protecting, from living
C. to protect, from living
D. to preventing, to live
Ⅰ级钢筋与钢板搭焊的接头型式应为（）。
A、E4316
B、F5003
C、E5003
D、E4303
