求一篇托福作文的思路. Is there a good reason to be rude(impolite) to another person?

interesting topic.
think of this question in the other way.
Is it always good to be nice to another person?
list the good reasons to be nice.then you might know some of the reasons to be rude in some situations.
this topic can be very deep.
we do not want to be rude,but at times we get rude any way.This is a form of releasing the negative emotional energy.If we feel angry,and suppress anger,it can be very unhealthy.And in the long run this suppressed anger would seek expression in an unconscious way which can be worse..
hope this enlightens you in some way.
good luck and let me know if I can be of further help