As part of the BBC World Service, BBC Learning English has been teaching English to global audiences since 1943, offering free audio, video and text materials to learners around the world.
LearnEnglish is brought to you by the British Council. It has hundreds of high-quality resources to help improve your English.
Analysing English Grammar by 
English Grammar in Use by 
Oxford English Grammar Course : a grammar practice book for intermediate and upper-intermediate students of English : with answers.
English Grammar in Use Supplementary Exercises by 
Check Your English Vocabulary for IELTS by 
English Vocabulary in Use Pre-Intermediate and Intermediate by 
Work on definitions. For each answer you get right, 10 grains of rice will be donated to the United Nations World Food Program.
Duolingo - Language Learning App for Apple, Android & Windows Phones
Duolingo is the world's largest online language learning platform and the most downloaded education app in the world for both Android and iOS devices. Duolingo has over 100 million users, is completely science- and data-based, and has gamified elements that make learning more fun.
Extensive multi-level, reading, writing, grammar, pronunciation and listening exercises to enable students to improve their English language skills.
Many links to hundreds of high-quality, FREE English learning sites and resources.
Short and easy explanations and exercises about grammar, reading, vocabulary, listening, pronunciation, slang, and idioms.
American English Pronunciation
Practice with minimal pairs with a link to http://www.manythings.org/lar/ Daily practice of sentences to improve intonation, rhythm, and pronunciation
Over 300 free videos on American English pronunciation and spoken English.
Authentic American Pronunciation
Videos and listening exercises.
Extensive multi-level, reading, writing, grammar, pronunciation and listening exercises to enable students to improve their English language skills.
Practice pronunciation of vowels.
751 video lessons by experienced native-speaker teachers. New classes are added three times a week, covering grammar, vocabulary, pronunciation,