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 wife invited some people to dinner. At...
A wife invited some people to dinner. At the table, she turned to their six-year-old daughter and said, "Would you like to say the blessing?"

"I wouldn't know what to say," the girl replied. "Just say what you hear Mommy say," the wife answered. The daughter bowed her head and said, "Lord, why on earth did I invite all these people to dinner?"