"Do you live in Mexico?"
Translation:¿Usted vive en México?
Maybe this is a silly question, but why isnt it vives? Is vivir irregular?
It's turning down "Vives en Mexico" (which should be a correct response) and suggesting "Vivis en Mexico" (I didn't think Duolingo used vosotros form). Reported 10/3/18
They are using the polite form of you which takes the third person singular.
It's an intuitive learning approach. If you like, also have open SpanishDictionary.com for quick reference to verb tables. 'Never too early to notice the pattern of the conjugations. For this DL question, we'd know where a friend lives, so the hint is to use the formal second-person form for "vivir".