DO YOU "WORK HARD" OR DO YOU "HARDLY WORK"?
This is something that creates a lot of confusion for Spanish people because although these phrases seem very similar they are, in fact, exactly opposite. If you "work hard" that means that you put in a lot of hours and make a lot of effort to improve your performance at work (this is the logical one).
If, on the other hand, you "hardly work" this means that you almost do nothing at all! If you are rich, for example, there may be no reason for you to work, so in that case you probably hardly need to work.
Hope that helps!
Soy el director de Daniel Smith + Partners. Tengo más de 10 años de experiencia enseñando inglés a españoles.