The teacher asked the students to bring one electrical appliance for "Show & Tell," and the next day every kid had something. The teacher asks Anna: What did you bring? "I brought a Walkman." "And what is it for?" "You can listen to music with it!" "That's nice. What did you bring Maria?" "I brought a can opener, it opens cans!" "Well done. Umm, Johnny, I see you didn't bring anything!" "Yes, I did. It's in the hall." So the entire class goes into the hallway. "Umm, Johnny, what is that?" "It's a heart / lung machine hospitals use to keep your heart going." "Whoa. What did your father say about you bringing this?" "He said, 'AAAARRRGGGH!!!'"