1.I houldn t have done it.我真不该那样做。 I shouldnt have done it. 用shouldn t have+过去分词表示类似责备或斥责的心情，表示不该、要是没。 That was a mistake./I blew it./I wish I hadnt done that. I really screwed up this time./I really messed up. I should have known better.
短对话 A:Oh, no!I shouldnt have done it.哦，不!我要是不那样就好了。 B:What did you do?你干什么了?
2.I houldn t have said that.我要是不说那话就好了. I shouldnt have said that. 用于说了不该说的话时。 I wish I wouldnt have said that.
短对话 A:I shouldnt have said that.我要是不说那话就好了。 B:Its too late now.现在后悔也晚了。
3 should have known.我早该知道了。 I should have known.I acted like a fool. I should have known better.
短对话 A:Hes married.他已经结婚了。 B:I should have known.我早该知道了。
4.It was careless of me to do so.做那种事，我也太不小心了。 It was careless of me to do so. careless表示没注意的、漫不经心的、粗自大意的。 It was thoughtless of me to do such a thing. It was hasty of me to do so./I was careless.
5. regret doing that.我后悔我做的事。 I regret doing that./I regret my action. I am sorry for what I have done.
情景对话 A:I regret I havent taken your advice.我后悔没有采纳你的建议。 B:Whats the matter?发生什么事了? A:Yesterday I came here to buy lottery and you suggested me choose three as the last number.昨天我来这里买彩票，你建议我后一个号码买3。 B:Yes.是的。 A:If I had listened to you, I would have got the highest price.如果我听了你的话，我就已经获得高奖金了。 B:Thus Im regretful too.那么我也后悔了。 A:Why?为什么? B: I should buy that number myself.我自己也应该买那个号码。 A:I regret doing that.我后悔我做的事。 B:I know what you mean.我明白你的意思。