Apostrophe Protection Society
Illustrates the correct use of the apostrophe in spelling the plural and possessive. Gives examples of misuse and the rules and examples for correct use.
http://www.apostrophe.org.uk/

Blue Book of Grammar and punctuation
Grammar and punctuation reference guide including exercises with answers.
http://www.grammarbook.com/

Canada-ESL.com
Free English activities and ideas on how to improve your English and free info about studying English in Canada.
http://www.canada-esl.com

Common Errors in English
Alphabetical listing of many words which are often used incorrectly. Includes explanations and examples.
http://www.wsu.edu/~brians/errors/errors.html

Electronic Flashcards: A Tool to Learn Languages
The site offers online tools to create, modify and study electronic flashcards in different languages.
http://earth.prohosting.com/newwords

English Bites
TV show focused on improving English language skills.
http://abcasiapacific.com/englishbites

English for Techies
By Christian Lassure, associate professor of English. For French student technologists. Grammar, false friends, translation methods, glossaries. Mechanical production engineering, industrial computing, and computer graphics.
http://www.english-for-techies.net/

English Page
Offers free grammar and vocabulary exercises, topical tutorials, reading exercises, dictionaries, and other resources for intermediate and advanced learners.
http://www.englishpage.com/

English Quizzes
Interactive, illustrated vocabulary and grammar exercises, rated according to difficulty.
http://www.prof2000.pt/users/tereza_n/

E-texts with Dictionary link
A collection of e-texts where every word is linked to a dictionary for vocabulary improvement.
http://www.thefreelibrary.com

Frank's ESL Restaurant
Crossword puzzles and links requiring a java-enabled browser. Includes bilingual puzzles inn Norwegian, Spanish and Italian.
http://frank_esl2000.tripod.com/

free ESL Mailing List
Free daily email. Increase your English learning skills and improve your English at the same time. Get expert help from teachers and language learners from around the world.
http://www.esl.com.ua

God Save the Subjunctive
Defines the subjunctive mood and gives links to more information, including example usage.
http://www.ceafinney.com/subjunctive/index.html

Indiana State University Grammar
Includes information on irregular verbs, modals, plurals, prepositions, tense and aspect, two-word verbs, and article usage.
http://isu.indstate.edu/writing/esl/esl.html

The Internet Grammar of English
Course written primarily for university undergraduates but useful for anyone as it doesn't presume any prior knowledge of grammar. Free for students who log in from a UK university and all explanations are free.
http://www.ucl.ac.uk/internet-grammar/home.htm

Language Games
Word search, crossword puzzles and hangman games for learning basic vocabulary. Games for learning other languages also.
http://www.languagegames.org/

Learn English Today
Free grammar and vocabulary section, idioms, exercises and links to news articles and recommended books.
http://www.learn-english-today.com

LearnEnglish.be
Aimed at the beginner and intermediate student. Includes grammar and vocabulary sections with additional exercises for practice.
http://www.learnenglish.be

Mister Mertens Online
Grammar and vocabulary explanations and exercises suitable for young learners or beginners of any age.
http://members.multimania.co.uk/mertensonline/

Professor Grammar
Includes games and a video grammar lesson. Requires RealAudio.
http://www.professorgrammar.com/

Sheppard Software - Free Vocabulary Web Games
Different vocabulary quiz activities covering over 2,000 words include SAT / GRE and other terminology.
http://www.sheppardsoftware.com/web_games_vocab.htm

Word Power
Offers phonics lessons, nursery rhymes, tongue twisters and Irish blessings for vocabulary practice. Oriented toward children with some exercises for adults.
http://www.wordpower.ws/

Word Surfing
A guide to ESL learners on the use of individual vocabulary development strategies using a well organised notebook. The method aims to encourage language learners to make the best possible independent use of all other available resources.
http://www.wordsurfing.co.uk