A lecture about English
A linguistics professor was lecturing to his English class one day. "In English," he said, "A double negative forms a positive. In some languages, though, such as Russian, a double negative is still a negative. However, there is no language wherein a double positive can form a negative."

A voice from the back of the room piped up, "Yeah, right."

A man and his Alligator
A man and his alligator walk into a bar and the man asks, "Does this bar serve lawyers?""Of course we do," replied the bartender."Great," said the man, "I'd like a beer... and give me a lawyer for my gator."