—The hall for international conferences is of great importance．
—I see, and we are sure to plete it on time．
A. built
B. to be built
C. having been built
D. building
网友回答
A. built
(答案→)B. to be built
C. having been built
D. building
解析：句意：--将要建造的召开国际会议的大厅是非常重要的。 --我明白了，我们一定要确保按时完成。done 被；to be done 将要被；doing 正在进行；having been done 已经被。故选择B。
考点: 考查非谓语动词的用法。