Can I help you ?   I need some stamps .   What kind of stamps do you want ?   How much do I need for this letter ?   I must weigh it .   How much ? Is it overweight ?   It is 5 grams overweight . Do you want to send it as an ordinary or registered letter ?   How much is it , then ?   Registration plus overweight , 7 yuan in all .   OK . Here you are . 