问题补充:
the program, they have to stay there for another two weeks.
A. Not completing
B. Not having completed
C. Not completed
D. Having not completed
答案:
A. Not completing
(答案→)B. Not having completed
C. Not completed
D. Having not completed
解析:考查现在分词的否定式,they和complete是主动关系,用现在分词做状语,not应放在doing/havingdone前,句意:没有完成计划,我们不得不再待两个星期。故选B。