建设项目总概算书是由该建设项目的各单项工程的综合概算书汇总而成的。( )
参考答案：错
When we hurried to the station, there happened ____ no bus at that time. [ ]
A. to have
B. to be
C. having
D. being
成功实施电子商务运行环境的秘诀有
