Bar

In a Bar, as a man was having a drink, a guy, apparently already with his load, approached him and said, "Would you bet a pint of beer that I can bite my own left eye?"
Thinking that this guy was really drunk, the first man agreed.
Then the supposed drunk guy took off his false left eye and bit it. The first man thought: "How could I let this guy to fool me?"
But a bet is a bet, so he bought the drunk guy a pint of beer and continued his drinking.
A few moments later, the same drunk guy approached the first man and said, "Would you bet a pint of beer that I can bite my own right eye?"
He thought to himself: Hey, this guy can't have both false eyes, right? So he accepted the bet. Then the drunk guy took out his false teeth and bit his right eye with them.