ABSTRACT
Part A Clerk: Good morning. What would you like to buy? Xiao Zhang: I want to buy water. How much is one bottle of water? Clerk: One bottle of water is two dollars and forty cents. Five bottles are ten dollars. Xiao Zhang: Well then, I’ll buy fi ve bottles. How much is cola? Clerk: A bottle of cola is also two dollars and forty cents. Do you want some? Xiao Zhang: Yes. I’ll buy two bottles.
