| at, Mrs. , don't, stand up, sit down |
A train stops at a station(车站). A young man wants to come out，but it is raining. A boy is standing under a big umbrella. The young man says to the boy，"Can you go and buy us two hamburgers，one for you and one for me？Here are two dollars(美元). " "Great！" says the boy and he goes to buy hamburgers. After some time，the boy is back. He is eating a hamburger. "Where is my hamburger?" asks the young man. "Oh，there is only one(只有一个) hamburger left(剩下). So I'm eating mine. Here is your dollar，"the boy says.
