That book takes fifty common errors, such as the confusion between “control” and “check” or “boring” and “bored” and illustrates them with humorous cartoons. The student sees exactly what he or she is saying from the illustrations and explanations of the incorrect and correct usage, which are shown side by side. It is divided into five sections, each with exercises to test the student`s knowledge. The book can be used by intermediate or advanced students and there is a full answer key, with explanations where necessary, so it is suitable for class or self-study.