Here are ADVANCED level (free) online courses...
English-online.org.uk's Advanced Course

ESL.About.com's Advanced Course



Wow!  Are you ready for headaches!?  These are the tests that gets you ready for TOEFL and the Advanced Certificate!

English-Test.net's DIFFICULT tests

a4esl.org's DIFFICULT GRAMMAR links

Look for the difficult links on Bergen.edu's Grammar Links



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To use these Quizzes, you need to register:
Englishconnection.com