问题补充：
They on the program for almost one week before I joined them,and now we 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：第一个动作发生在“我” 加入之前，又由于现在还在做，所以它的时态应用过去完成进行时；now证明第二个空格与现在有关，所以满足条件的只有A项。
