If you are learning English or want to improve your ability to use Standard English, then this book is important to you. It is designed to test and help improve your grammar usage and avoid common embarrassing grammar mistakes often made in public when correct grammar matters. It consists of two parts: Basic grammar rules are explained, then five hundred and thirty examples with common grammar errors for correction grouped in 10] are given in Part 1 - Find the Mistakes. The second part, Part 2 - Corrected, shows the corrected grammar for each of the examples in part one, with the reason, or reasons, for the correction clearly indicated. It should be fun for you, or anyone who is student or user of the English Language, to find the mistake or mistakes in each sentence, in the first part, then check the answers in Part 2. You will have the satisfaction of seeing how sharp you are, or how much more you need to practice these exercises. This book comes form the author's experience of teaching English to students of varying ages and backgrounds. Its publication has been prompted by his commitment as teacher and the prevalence of these grammar mistakes in situations requiring the use of Standard English. Going over the examples with answers in this book, will help you develop greater understanding and confidence, and to be a better student, speaker and writer of Standard English when required.