Questions: Who is right, Jack or Tom? 

The big one or the small one?  

      Tom and Jack are good friends. Sometimes they are friendly to each other, but sometimes they are not.

     One day they went out for a walk. At noon they were hungry and went to a restaurant for lunch. Tom said, “Please bring us two oranges first. ”When the waiter put two oranges on the table, Jack took the big one. Tom got unhappy, “You are not polite, Jack. Why don't you take the small one?” Tom said. 
     “But I am right,” said Jack with a smile. “If I let you take first, which one will you take?”  
     “Of course. I'll take the small one,' said Tom. “Yes,” Jack said, “If you take the small one, the big one will still be mine. Don't you think so?” 

     “Oh---“Tom couldn't answer.