Theyon the program for almost one month before l was arranged to help them. Now weon it a

问题补充：

Theyon the program for almost one month before l was arranged to help them. Now, weon it as no result has come out.

A. had been working: are still working

B. had worked; were still working

C. have been working; have worked

D. have worked; are still working

答案：

(答案→)A. had been working: are still working

B. had worked; were still working

C. have been working; have worked

D. have worked; are still working

解析：句意：在我被安排帮助他们之前，他们一直在忙于这个项目。现在我们还在做这个项目，没有结果。第一空的动作发生在before l was arranged to help them.是过去的过去的动作，用过去完成进行时，第二空是现在正在发生的动作，用现在进行时，选A。