I was in the language threads and I saw specific people asking for specific help
Not unreasonable that you should do the same. You did specifically ask for "good" sites. I quite like these sites, they don't require too much brain power.
[polishgrammar.com] - Polish Grammar
[goethe-verlag.com/tests/EO/EO.HTM] - Goethe Verlag, English/Polish Multiple-Choice Tests