题目内容：

My father got very angry______ A.with that I had done B.with what I had done C.At that I had done
My father got very angry______
A.with that I had done
B.with what I had done
C.At that I had done
D.at what I had done

优质解答

正确答案是 B. with what I had done
angry with what I had done 为我（已）做的事而生气

追问：

什么时候用that？

追答：

what 有 that which 的意思 按语法，如果用 that ， 正确说法是 angry at that which I had done （但这是非常规说法）。 句子和 what I had done got my father very angry 一样， 明白这点就会明白为什么答案是 what I had done。