Mary was almost crazy with her three kids. She complained to her best friend, "They're driving me nuts. Such pests, they give me no rest."

"What you need is a playpen to separate the kids from yourself," her friend said.

So Mary bought a playpen.

A few days later, her friend called to ask how things were going.

"Superb! I can't believe it," Mary said. "I get in that pen with a good book and the kids don't bother me one bit!"