--- Mary was crying sadly.
--- Oh, she ______ the bad news that her mother was badly injured in the accident.A.must knowB.might have knownC.must have knownD.should have known
网友回答
C解析考查虚拟语气.句意:玛丽哭得很伤心._哦,她一定是知道了她的母亲在车祸中严重受伤的坏消息了. “must+have+done”表示对过去事情的肯定推测，译成“一定做过某事”，该结构只用于肯定句。结合语境可知选C