I couldn't resist: I saw this quizz on catw's journal,
http://www.helloquizzy.com/tests/the-commonly-confused-words-test.
My results below. I thought my results would be even better, because I am extremely good in spelling, but no. English always beats us non native "speakers".
You scored 100% Beginner, 86% Intermediate, 93% Advanced, and 73% Expert!
You have an extremely good understanding of beginner, intermediate, and advanced level commonly confused English words, getting at least 75% of each of these three levels' questions correct. This is an exceptional score.