tenses

1. http://www.englishpage.com/verbpage/verbtenseintro.html
2. http://www.englishclub.com/grammar/verb-tenses.htm
3. http://www.englisch-hilfen.de/en/grammar_list/zeitformen.htm
4. http://www.ego4u.com/en/cram-up/grammar/tenses
5. http://www.bbc.co.uk/skillswise/words/grammar/tenses/getting_the_right_tense/

homonyms

1. http://grammar.about.com/od/fh/g/homonymterm.htm
2. http://www.editingandwritingservices.com/homonyms.html
3. http://www.worsleyschool.net/socialarts/synonyms/page.html
4. http://www.cooper.com/alan/homonym_list.html/homonym.html

homophones

1. http://www.englishclub.com/pronunciation/homophones-what.htm
2. http://www.bifroest.demon.co.uk/misc/homophones-list.html
3. http://www.learnenglish.de/homophones/Homophones.htm

parts of speech

1. http://www.englishclub.com/grammar/parts-of-speech_1.htm
2. http://www.english-grammar-revolution.com/parts-of-speech.html
3. http://grammar.about.com/od/basicsentencegrammar/a/POS.htm
4. http://www.really-learn-english.com/english-parts-of-speech.html

british/american english

1. http://www.bg-map.com/us-uk.html
2. http://www.englishclub.com/vocabulary/british-american.htm
3. http://esl.about.com/library/vocabulary/blbritam.htm
4. http://www.woodlands-junior.kent.sch.uk/customs/questions/americanbritish.html
5. http://esl.fis.edu/grammar/easy/aebe.htm

prefix ans suffix

1. http://ueno.cool.ne.jp/let/prefix.html
2. http://www.englishclub.com/vocabulary/prefixes.htm
3. http://www.michigan-proficiency-exams.com/prefix-suffix.html
4. http://www.learnenglish.de/grammar/prefixtext.htm
5. http://www.learnenglish.de/grammar/prefixtext.htm
6. http://dictionary.reference.com/browse/suffix
7. http://www.learnenglish.de/grammar/suffixtext.htm
8. 
   
9. http://www.michigan-proficiency-exams.com/suffix-list.html

syllabification

1. http://www.printablereadinggames.com/room2/4inarow/phonics_game2.htm
2. http://www.englishclub.com/esl-forums/viewtopic.php?f=139&t=52165
3. http://teacher-toolbox.blogspot.com/2007/05/free-reading-games-word-activities.html
4. http://learnspeakingenglish.blogspot.com/2010/01/syllabification.html
5. http://www.ehow.com/list_6634889_basic-syllabication-rules.html