The title says it all!
I think it depends on your goals. Italki good for language but I have never seen anything better than coursera.org for science.
www.howjsay.com (Pronunciation Dictionary)
http://www.elllo.org/english/0001.htm
Information on the TOEFL Exam @ the "ets" website @ http://www.ets.org/toefl/ibt/about
http://www.urbandictionary.com/
TED Lectures @ http://www.ted.com/
The Kindergarten through 12th Grade Reader can be a great resource for learning.
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PARTS OF SPEECH:
The "Mr. Morton" cartoon @:
http://grammar.ccc.commnet.edu/grammar/grammarrock.htm#predicates
Pronouns:
http://www.english-grammar-revolution.com/list-of-pronouns.html
.
' ADJECTIVES to describe people:
.
http://www.enchantedlearning.com/wordlist/adjectivesforpeople.shtml
.
ONLINE STUDY LINKS for English
http://www.mes-english.com/phonics/dolch.php (Best Collection of DOLCH WORD LISTS)
http://www.spellingcity.com/which-word-best-completes-the-sentence.html?listId=18026286
http://en.wikipedia.org/wiki/Dolch_Word_List
http://www.englishpractice.com/ (very good)
http://www.myenglishpages.com/site_php_files/grammar-exercise-either-or-neither-nor.php#.U--6CPfna74 (either/or)
https://www.youtube.com/watch?v=3dasuQ9u8i0 (Vowel explanations)
https://www.youtube.com/watch?v=MzhjD-XrYjg (How to pronounce CONTRACTIONS)
http://www.englishlanguageguide.com/grammar/preposition.asp
http://www.myvocabulary.com/dir-root-root_master
http://www.oxforddictionaries.com/words/i-or-me
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Test your Level of English Grammar/Vocabulary
GreenwichMeanTimeDOTcom
http://wwp.greenwichmeantime.com/time-zone/europe/switzerland/
ONLINE STUDY LINKS for English
http://www.mes-english.com/phonics/dolch.php (Best Collection of DOLCH WORD LISTS)
http://www.spellingcity.com/which-word-best-completes-the-sentence.html?listId=18026286
http://en.wikipedia.org/wiki/Dolch_Word_List
http://www.englishpractice.com/ (very good)
http://www.myenglishpages.com/site_php_files/grammar-exercise-either-or-neither-nor.php#.U--6CPfna74 (either/or)
https://www.youtube.com/watch?v=3dasuQ9u8i0 (Vowel explanations)
https://www.youtube.com/watch?v=MzhjD-XrYjg (How to pronounce CONTRACTIONS)
http://www.englishlanguageguide.com/grammar/preposition.asp
http://www.myvocabulary.com/dir-root-root_master
http://www.oxforddictionaries.com/words/i-or-me
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Test your Level of English Grammar/Vocabulary
http://www.examenglish.com/leveltest/grammar_level_test.htm
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