A:Execuse me,may I take you a few minitues?
B:Oh.Yes?
A:Here we have a new type of Colgate toothpaste.Would you like to have a try?
B:Can you introduce the advantage of it to me?
A:Of course!It is not only clean your but also can white you teeth and make you feel fresh.
B:That sounds good!I want to have one.
A:Ok,3$ one tube.
B:Here you are.
A:Thank you very much,see you,bye!
B:Bye!