This book has had a long gestation. The idea was inspired by the chapter title “Do You Make These 100 Common Errors in English?” taken from one of the many books written by the late Herbert V Prochnow, former president of the First National Bank of Chicago.

I am indebted to Edward Rosenheim, the distinguished editor of this book, for the vision and direction he gave at critical points in the planning and writing. I am grateful to Tracy Weiner, associate director of the University of Chicago Writing Program, for creating the various test sections, which provide invaluable reinforcement and a welcome sense of humor. Barbara Stufflebeem, a freelance editor and former student of Edward Rosenheim’s, also made valuable contributions to the manuscript.