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Vital Books for EFL Teachers
The Practice of English Language Teaching (3rd Edition) (Longman Handbooks for Language Teachers)The Practice of English Language Teaching (3rd Edition) (Longman Handbooks for Language Teachers) by Jeremy Harmer
Buy new: £22.54 / Used from: £16.50
The clearest, most concise, yet all-encompassing guide to ELT
About Language - Tasks for Teachers of English (Cambridge Teacher Training and Development)About Language - Tasks for Teachers of English (Cambridge Teacher Training and Development) by Scott Thornbury
Buy new: £14.61 / Used from: £11.43
Work through this and you will have covered the entire language analysis syllabus for the Cambridge DELTA and still have a great reference for later!
Keep Talking: Communicative Fluency Activities for Language Teaching (Cambridge Handbooks for Language Teachers)Keep Talking: Communicative Fluency Activities for Language Teaching (Cambridge Handbooks for Language Teachers) by Friederike Klippel
Buy new: £12.20 / Used from: £9.98
The best speaking practice book in the world ever. Honestly. It's hard to use at first, but once you've worked out the system, it's invaluable.
Grammar Practice Activities: A Practical Guide for Teachers (Cambridge Handbooks for Language Teachers)Grammar Practice Activities: A Practical Guide for Teachers (Cambridge Handbooks for Language Teachers) by Penny Ur
Buy used from: £6.16
All those activities for grammar you were looking for in one book.
Practical English Usage (2nd Edition)Practical English Usage (2nd Edition) by Michael Swan
Buy used from: £9.99
The only grammar reference an EFL teacher will ever really need. Others are more comprehensive, but this covers every question a student could ever ask you. Really.
Sound Foundations (Teacher Development)Sound Foundations (Teacher Development) by Adrian Underhill
Buy used from: £14.95
A thoroughand useful introduction to phonology and how to teach it.
Teaching Tenses: Ideas for Presenting and Practising Tenses in EnglishTeaching Tenses: Ideas for Presenting and Practising Tenses in English by Rosemary Aitken
Buy new: £16.57 / Used from: £18.00
Helps you through the maze that is the English tense and aspect system, with practical ideas for contexts and learner difficulties.