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."

Being hurt
A husband and wife went to the fairgrounds. The wife wanted to go on the Ferris wheel, but the husband wasn't comfortable with that. So the wife went on the ride by herself.The wheel went round and round and suddenly the wife was thrown out and landed in a heap at her husband's feet."Are you hurt?" he asked."Of course I'm hurt!" she replied. "Three times around and you didn't wave once!"