"When do you learn Vietnamese?"
Translation:Bạn học tiếng Việt khi nào?
The above translation was not one of the choices. The correct answer was "luc nao" (my computer does not have accents). This is the first time this has been introduced and i've completed the question section (i'm doing a review). Can someone please explain what this is and how is it different from "khi nao"?