点焊的基本循环包括()
A、预压
B、焊接
C、维持
D、休止
参考答案:A, B, C, D
All the doctors in the hospital insisted that he_____ badly wounded and that he______ at once.
A.should be; be operated on
B.were; must be operated on
C.was; should be operated
D.was; be operated on
关于合称坡度的控制作用说法()正确的是。
A.当陡坡与小半径平曲线重合时,在条件许可的情况下,以采用较小的合成坡度为宜
B.冬季路面有积雪结冰的地区,其合成坡度必须小于8%
C.自然横坡较陡峻的傍山路段,其合成坡度必须小于8%
D.非汽车交通比率高的路段,其合成坡度必须小于8%