题目内容：

His mother is ill in hospital yesterday.He____look after her.A.needs to B.needs C.has toD.had to

优质解答

D
不得不
前后时态要一致
(注：楼主所给的题目时态打错了,应该是：His mother was ill in hospital yesterday.He____look after her.因为yesterday‘昨天’,已经过去,应该用过去时.）