An American, a Canadian, a young attractive woman and an old lady were on a train

As they went through a tunnel and it became too dark to see and a loud SMACK could be heard. As the train exited the tunnel everyone looked at the American and saw he had a bright red cheek. The old lady thought to herself "I bet that American grabbed that young woman and she smacked him for it." The young attractive woman thought "I bet that American grabbed that old lady thinking it was me and she smacked him for it." The American thinks to himself "I bet that Canadian grabbed that young attractive woman and she smacked me thinking it was me." And the Canadian thinks to himself "I hope we go through another tunnel so I can smack the American again."