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 farmer and his wife went into town for...
A farmer and his wife went into town for their yearly medical checkup. After he was finished, the doctor asked to speak with the wife alone. In the doctor's office, the doctor told her that her husband had a very serious disease. He must not have to undergo stress in anyway, the doctor said. You must do all of his chores for him, and make him nice meals 3 times daily.

You must be available for him, and do things with him, such as watch sports games with him. Do not do anything that would cause him to get upset for any reason. Without this kind of special treatment, he will die. You must do this for at least 10 months to a year. At that time he will need another check-up, at which point he will probably be alright again.

Later, on the way home, the farmer asked:"what the doctor tell you?"

She said, "You're going to die."