On October 31, Americans celebrate Halloween. Kids dress up in costumes and go door to door, saying "Trick or treat!" People then deposit into their bags or plastic pumpkins a piece of candy -- most often a piece of chocolate. The kids -- at least the polite ones -- say "thank you" and move on to the next house. It's an American tradition that's been going on since the 1920's ... and going stronger than ever! We're happy to help you get in the spirit of Halloween with this selection of spooky idioms.