One day Susan Li was walking along the street when she saw her friend Lisa Wu.She had not seen her old friend for some time so she said,"We've got lots to talk about.Let's have some tea and cake in that cafe."She pointed to a nearby cafe.Lisa agreed,so the two friends went into the cafe.Susan ordered."We'll have two pieces of cake,"she said,"and a pot of tea."The waitress wrote down their order and went away.She soon returned with the cake and the pot of tea.Susan saw immediately that one piece of cake was a little bigger than the other.However,she was well-mannered so she picked up the plate and offered it to Lisa .“Have a piece of cake,Lisa,"she said."Thank you,"But after you.""No,no,"Susan said."After you,please.""Very well ,"Lisa said and she took the bigger of the two pieces of cake.Susan was very angry."You've taken the bigger piece of cake,"she said."That was very rude.""Not at all,"Lisa replied.""Tell me,if you had taken the cake before me,which cake would you have taken?""The smaller one,of couse,"Susan said."Exactly.Well,you've got the smaller one,so what are you complaining about?"