Question

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 worked; were still working           D．have worked; are still working

Answer 1

A

解析:

A 此题考查的是时态问题。从before引导的从句中的过去时态可知主句的时态应为过去完成时。故排除C、D。now一词提示用现在进行时，表示“他们一直工作了一周”，强调动作的连续。