第28题: [单项选择]The whole building ______ burned down. But the heavy rain ______. A. might have been; had helped B. could have been; helped C. was; could help D. must have been; help 参考答案:B 答案解析:[分析] 句意为:整栋楼可能都已经烧掉了,但幸亏那场大雨救了急。本题考查的是虚拟语气用法,could have been意为“有可能已经……”。例:If I hadn't warned you,you