AskOxford: the free online dictionary resource from OUP - Search the Compact Oxford English Dictionary; get answers to questions on English, grammar, spelling, dictionaries and usage; improve your writing skills; try our word games, crosswords and puzzles; learn French, German, Spanish, and Italian.
English Grammar - English Club Grammar section provides English grammar lessons for students and teachers, offers references, quizzes, lessons and tips.
Explanatory dictionary of English language - Online English dictionary, thesaurus and reference guide. A multi-source dictionary search service that includes explanatory dictionary of the English language and pronunciation engine.
Glossary of Internet Terms - Glossary explains terms and sayings that often appear in internet and in habitual internet users' speech.
Glossary of linguistic terms - Glossary of linguistic terms discovers those concepts and terms you were looking to understand.
Phonetics of the English language - Guide to phonetics of the English language. Vocal anatomy, sound properties, pronunciation, general and acoustic phonetics.