best friend seems anxious a lot,she bites her fingernails an

Dear worried,I think your friend need to relax,maybe you can have chat with her and ask if she has any problems,you can tell her that you are willing be help her。Well,biting fingernails is not a good habit,you can tell her that there some dirty things in our fingernails and they can cause illness,moreover,biting fingernails is not polite。For my part,you have to know her better,you should try to understand her 。You can tell her that we should learn to be independent and try to look after ourselves。When you talk to her,you must be patient and gentle,remember,don't be rude。Hope my suggestion will work out!Best wishes!Help (希望我这篇文能帮到你,虽然你上面的题目写得不清楚,但我估计是worried写信求助,然后要求你以Help的身份回信)