Question

They _________ on the program for almost one week before I joined them, and now we are still working on it as no good results have come out so far.

A．have worked	B．had worked
C．have been working	D．had been working

Answer 1

D

考查时态。句意：在我加入他们之前，他们一直在这个项目上工作了将近一个星期。结合语境可知本句描述的在过去已经完成的正在进行的动作，故用过去完成进行时态，选D。