Triple A is a contrastive exercise book for the intermediate and advanced levels, focusing on some major differences between Swedish and English grammatical structures. The sentences are taken from a great variety of texts, produced by American, British and Swedish writers and speakers, but most of the translations are from Swedish into English. Nearly all of the 15 chapters include an introduction where the problems to be dealt with are discussed. The key gives detailed comments on the translated structures. Triple A also contains two Appendices with practical "backward" exercises starting from grammatical terms; in these exercises the students are asked to produce texts to meet given conditions.