A：Hi，Susan．Are you interested in buying some used books？You can really save some money．
B：（51）___
A：Er…Let me see．I have a science book called Today's World，and I’m selling it for 30dollars．
B：（52）___
A：Maybe so，but I bought it for 60，and I put lots of notes in it．That should help you．
B：（53）___
A：Oh，I’ve got an English writing textbook for 14dollars，a math book for 23and a novel for only 7．
B：Er…．
A：You know，these things go fast．（54）___
B：Well…，OK，I’ll take the writing textbook and the novel．I need both of them for sure．
A：No more textbooks？
B； （55）___Teachers are always changing their minds about textbooks．
A：All right．Here are the books you need，21dollars in total．
B：OK．Here is the money．
A．Not now．
B．It’s up to you．
C．That sounds great．
D．Well，what do you have？
E．What else are you selling？
F．How much do I need to pay you？
G.30？That’s too expensive for an old book like that．
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