needn't have done和didn't need to do 有什么不同?

needn't have done和didn't need to do 有什么不同? didn't need to do 与needn't have done 的区别和相同点 Didn't need to do还有 needn't have done的区别 need to do sth,need do sth.needn`t do sth和don`t need有什么不同! needn't 和 don't need to 有什么不同? needn't needn't have done 和don't need to 的区别 didn't need to和和need't have done什么区别? Needn't have done 和needn't do的区别! needn't have done还是didn't have done needn't和don't need to有什么区别?haven't和 don't have 有 请问:hadn't done 和hasn't done 和has to do 有什么不同? 有没有didn't have to do ,didn't need to do