骨与关节结核最常见的发生部位（）。
A.脊柱椎体
B.膝关节
C.髋关节
D.踝关节
E.腕关节
参考答案：A
--- Jack, could you help me ________ these pictures on the blackboard? It may help us know more about the hazy weather. (雾霾)
--- With pleasure.
A．put in
B．put up
C．put on
D．put down
碳素钢焊条型号E4303中的前两位数字“43”表示熔敷金属抗拉强度的最大值为430Mpa。（）
