题目内容：

The man needed_,for one of his legs was badly injured.
A,to look after B.looking after C.look after D,being looked after

优质解答

B
need doing 需要被...
这里意思是 需要被照顾
所以就是 need looking after

追问：

那D是什么时态啊？ 那need to do又解释什么呢？