题目

They____on the program for almost one month before l was arranged to help them. Now, we____on it as no result has come out. 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：A 【解析】 试题分析：句意：在我被安排帮助他们之前，他们一直在忙于这个项目。现在我们还在做这个项目，没有结果。第一空的动作发生在before l was arranged to help them.是过去的过去的动作，用过去完成进行时，第二空是现在正在发生的动作，用现在进行时，选A。 考点：考查时态

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