Can anyone help me regarding the correct use of "gratis" vs. "gratuito"? While traveling and studying abroad, I've never been told that I've used them incorrectly, yet I can't seem to come up with an explanation that sticks for my students. The use of "gratuito/-a" as an adjective is okay, but other times their writing sounds incorrect to me and I'm not easily able to explain the reason to them. The "libre" and "liberado" deal is no problem, by the way. Thanks so much!