Practice and Quiz:
http://lampang.thcity.com/quiz/indexo.html (For Thai learners)
http://members.aol.com/eslkathy/esl.htm
http://members.shaw.ca/jack-higa/prototype/SB10.htm
http://owl.english.purdue.edu/handouts/interact/index.html
http://parapal-online.co.uk/
http://towerofenglish.com/writing.html
http://web2.uvcs.uvic.ca/elc/studyzone/grammar.htm
http://www.agendaweb.org/
http://www.autoenglish.org/
http://www.better-english.com/easier.htm
http://www.churchillhouse.com/tests/index.html
http://www.easyenglish.com/
http://www.englishforum.com/00/interactive/
http://www.englishjet.com/english_courses_files/tests.htm
http://www.englishladder.com/
http://www.forumeducation.net/
http://www.manythings.org/voa/
http://www.nonstopenglish.com/allexercises/
http://www.rong-chang.com/quiz.htm
http://www.ruthvilmi.net/hut/LangHelp/Grammar/interactive.html
http://www.scientificpsychic.com/engtst1.html
http://www.smic.be/smic5022/
http://www.testpodium.com/en/main/englischtest_02.asp
http://www.world-english.org/
http://www.wsl.edu.pl/~azetka/