The police ____(search) for the thief these days ,but they haven't found him yet

问题描述:

The police ____(search) for the thief these days ,but they haven't found him yet

have been searching
从下文 but they haven't found him yet(可他们还没找到可见,这个动作还在进行之中,故用现在完成进行时
请在客户端右上角评价点“满意”即可,为什么不是were searching呢?从状语these days (这些天) 和下文they haven't found 。。。。这个时态可见,陈述的是现在的事, 不能用过去进行时, 这样时态不一致