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 此題考查的是時(shí)態(tài)問(wèn)題。從before引導(dǎo)的從句中的過(guò)去時(shí)態(tài)可知主句的時(shí)態(tài)應(yīng)為過(guò)去完成時(shí)。故排除C、D。now一詞提示用現(xiàn)在進(jìn)行時(shí)，表示“他們一直工作了一周”，強(qiáng)調(diào)動(dòng)作的連續(xù)。