The sentence is perfectly correct. (Wasn't this asked just a day or two ago in a slightly different form?) If you click
http://www.yourdictionary.com/ahd/e/e0262500.html
a link will take you to the appropriate page of the YourDictionary website. Once there, you'll see that one of the key meanings of the word except' is 'other than', so all you need do is ask yourself this question: Is it OK to say 'Do you know any languages
other than English?' If the answer is 'Yes' - which it is - then using 'except' in the same position must be OK, too.