You know what? Even people who's native tongue is English do not have a perfect grammar, even famous American celebrities The best way to master any language is to always use it and be confident when speaking it. If you think you made a mistake, that's okay, it's normal, nobody's perfect. Also, try to read books, watch English movies and TV series and try to apply the jokes or phrases you will pick up. The best way to lear is to keep on practicing.