请问needn't和 haven't to的区别

needn't 可以用的表示不必
you needn't worry. 是完全可以的
haven't to 不对的,应该用 don't have to 表示不必
you don't have to worry 也是可以的
看了补充回答如下
needn't主观不必
you need't go.（说话人主观认为）你不必去.
don't have to客观不必
you don't have to go (目前实际情况就是)你不必去.
第二句与说话人自身的态度无关