One possible version :
An air hostess failed to meet a passenger's requirement,which made him very angry.Although the
passenger refused to pay heed to the air hostess,she still served him politely with a smile.Her sincere
smile touched the passenger,who finally chose to forgive her.
From where I stand,I am fully convinced that smiles play a significant role in our lives.To start with,
a smile is a relief to one's anxiety.Besides,a smiling face never fails to cheer up those around us.
For me,the smile from my mother is the most beautiful one that I will always treasure in my life.
Once I failed in a math exam,which made me very sad,I had been crying for a whole afternoon since
math was always my best subject.Knowing what had happened,mom came by my side.What I saw
was mom's sincere smile,the one telling me not to give up and encouraging me to go on fighting.
As the old Chinese saying goes,a smile makes a person become younger.A smile costs none but
means a lot.Please have a smile.