Dearworried,Ithinkyourfriendneedtorelax,maybeyoucanhavechatwithherandaskifshehasanyproblems,youcantellherthatyouarewillingbehelpher.Well,bitingfingernailsisnotagoodhabit,youcantellherthattheresomedirtythingsinourfingernailsandtheycancauseillness,moreover,bitingfingernailsisnotpolite.Formypart,youhavetoknowherbetter,youshouldtrytounderstandher.Youcantellherthatweshouldlearntobeindependentandtrytolookafterourselves.Whenyoutalktoher,youmustbepatientandgentle,remember,don'tberude.Hopemysuggestionwillworkout!Bestwishes!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)