A:can I heIp you?
B:I want to buy a pen
A:which colours do you like
B:Oh ,let me see...
A:How about the red one?
B:It is too big for me .
A:How about the blue one?
B:I do not like the colour.
A:And how about the green one?
B:Yes,it is a nice pen .
How much is it
A:It is ten Yan.
B :Here you are
A:Thanks
B:Good bye
A:Good bye