问题补充：
They on the program for almost one week before I joined them, and now we on it as no good results have come out so far.
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：考查时态。根据句意：在我加入他们之前，他们已经在这个项目上进行了一周时间。现在我们依然在努力，因为到目前为止还没有什么好的结果。第一个空work的动作发生在joined之前，而且动作依然在继续，所以用过去完成进行时。第二个空有now这一时间状语，用现在进行时。所以答案选A。
