将焊条与工件保持一定的距离,然后()落下,使之轻轻敲击工件,发生短路,再迅速将焊条提起即产生电弧的方法,称为敲击法。
A.水平
B.垂直
C.自由
D.倾斜
参考答案:B
The new stadium being built for the next Asian Games will be ______ the present one. [ ]
A. as three times big as
B. three times as big as
C. as big as three times
D. as big three times as
海上运输货物保险一般货物费率按不同的运输方式分为()。
A.铁路运输和汽车运输
B.三种
C.海运、陆运、空运和邮包
D.低、中、高三个级别