---I’m sorry! I would have taken him to hospital if I had known he was seriously ill.
--- But .
A. you didn't
B. you hadn't
C. he wasn't
D. you aren't
网友回答
(答案→)A. you didn't
B. you hadn't
C. he wasn't
D. you aren't
解析：
试题分析:考查动词时态。从上句的虚拟语气可知说话人是对过去已经发生事情的后悔遗憾，所以回答应该是针对过去的事实。句意：---真对不起！如果我知道他病得严重的话我就带他去医院了。---可是你没有。故A选项正确。