Book excerpt: What is sold at garage sales? Why does no one get wet at a bridal shower? For non-native speakers, here's a humorous approach to understanding common American customs and the expressions related to them. Customs are explained, one to a page, with conversational examples and whimsical cartoons. Topics range from age-old traditions, such as shaking hands and bachelor parties, to more modern American practices--coupon clipping, TV dinners, and tailgate parties.