Translate an English joke

I ate mine.

A train stopped and many people got off to buy food and fruit. A young man wanted to buy it, but it began to rain. A boy is standing under a big umbrella. The young man said to the boy, "Here are two dollars. Can you buy me two hamburgers? " One for you and one for me. "

"Great!" The little boy said, and then went to buy hamburgers. After a while, the little boy came back with a hamburger in his mouth.

"Where's my hamburger?" The young man asked.

"Ah, there is only one left, so I want to eat mine. This is your money. "