【多选题】In most Americans’ mind, Black Friday is a _______day.
B.
The busiest shopping day of the year
C.
A day to turn a profit for businessman
D.
the beginning of Christmas shopping season
【单选题】Black Friday is the Friday after Thanksgiving Day.
【单选题】Black Friday is a _______ day.
【判断题】采取措施预防坡道或者台阶光滑。在台阶边沿使用低摩擦材料有助于防滑。
【单选题】在机件穴蚀的同时,金属表面还产生(),两种腐蚀交替进行共同作用致使机件穴蚀破坏。
【判断题】Black Friday is the day after Christmas.
【简答题】预制打入桩垂直度偏差应控制在( )以内。入土深度控制,对摩擦桩应以( )为主,以( )作为参考,端承桩应以( )为主。