A. How many stamps do you need?
B. I want to buy some stamps and postcards.
C. It's two yuan for one stamp, and it's one yuan for one postcard. That's twenty-five yuan.
D. Five.
E. To the post office.
F. Ten.
G. How many postcards do you need?
H. How much are they?
I. Where are you going?
J. What do you want to do?
正确顺序为：
Mary: Hello, Lucy! What are you doing?
Lucy: I am sending some postcards. How about you?
Mary: I'm sending a letter. Where are you sending your postcards?
Lucy: I'm sending them to America. And where are you sending your letter?
Mary: I'm sending it to Canada.
Lucy: How much are the stamps?
Mary: I think they are ten yuan or more.
Lucy: That's too expensive (昂贵的).
Mary: I think so.
Lucy: Why not send an email on the computer?
Mary: That's a good idea. Let's go and find a computer.
Lucy: Can you write an email?
Mary: Yes, I can.
A. postcard
B. computer
C. idea
D. stamp
E. email