党的群众路线教育实践活动主题是（）。
A、为民
B、务实
C、清廉
参考答案：A, B, C
三级耐火等级民用建筑每层最大允许建筑面积为（）平方米
A.1000
B.6600
C.6700
D.6800
The bus hit against a tree in the fog and __________to the deep valley, with ten passengers killed and twenty wounded.
A．down did it roll
B．down rolled it
C．down it rolled
D．it down rolled
