mustn't/needn't/shouldn't有什么区别?请举一些例句，方便我的理解，

mustn't/needn't/shouldn't有什么区别?请举一些例句，方便我的理解，
mustn't/needn't/shouldn't有什么区别?
请举一些例句，方便我的理解，

mustn't/needn't/shouldn't有什么区别?请举一些例句，方便我的理解，
mustn't不许
You mustn't forget your homework.你绝不能忘了你的作业.
needn't不需要
You needn't to wait for such a long time.你不需要等这么久.
shouldn't不应该
You shouldn't lie to us.你不应该对我们说谎.

mustn't不许
needn't不需要
shouldn't不应该
主要就是意思不一样