Practical English Usage is a guide to problems of this kind. It deals with over 600 points which regularly cause difficulty to foreign students of English. It will be useful, for example, to a learner who is not sure how to use a particular structure, or who has made a mistake and wants to find out why it is wrong. It will also be helpful to a teacher who is looking for a clear explanation of a difficult language point. There is very full coverage of grammar, as well as explanations of a large number of common vocabulary problems. There are also some entries designed to clarify more general questions (e.g. formality, slang, the nature of standard English and dialects) which students and teachers may find themselves concerned with.