问题
完形填空
—Was the driving pleasant when you went to Mexico last summer?
—No, it ________ (rain) for four days when we arrived, so the roads were very muddy.
答案
had been raining
考查时态。答句句意:在我们到达之前下了四天的雨,道路异常泥泞。表示在过去某一动作之前一直在进行,并有可能继续下去的动作,用过去完成进行时。