Learning to use idioms naturally, in an appropriate context and tone, is a key to mastering truly expressive English. This book covers about 1000 most frequently used idioms. They are invaluable additions to the learner's knowledge of English. 'What You Need to Know about' is and open-ended series of ELT reference books on various aspects of English specially planned for intermediate learners who want to get to grips with English. Covering the most important topics of English, the series aims at helping foreign learners build a solid foundation for the learning of the language.