A dictionary of problem points in the English language as encountered by learners and their teachers. Common problems are solved with practical, clear information in over 600 entries. It contains an extensive research with current users of the book, besides this, it has new features that make it easier for users to find their way around the book; all the most popular entries are retained, but almost all the entries have been modified to make them clearer and more effective in solving readers' problems; explanations and examples now based on current corpus research; new entries on 'Kinds of English', covering standard English and dialects, correctness, spoken and written English, formality, and variation and change.