下列材料的牌号中属于低碳合金高强度结构钢的是()。
A.Q215
B.Q235
C.Q295
D.Q345
E.Q390
F.T9
G.Q460
参考答案:C, D, E, G
My mother asked you _______ when you come back.[ ]
A. ring up her
B. ring her up
C. to ring up her
D. to ring her up
简述饭店的主要作用