X线中心线以外的线称（）
A.平行线
B.垂直线
C.轴线
D.斜射线
E.中心线
参考答案：D
He has been doing the job for many years, but has never felt ________ it, though his workmates think it is a ________ one．
A．tired of; tired
B．tired of; tiring
C．tiring of; tired
D．tiring of; tiring
建筑钢材的强度指标，一般采用()试验获得。
A.抗拉
B.抗压
C.抗剪
D.抗冲击
