"We are athletes, not lawyers."
Translation:Mi sportolók vagyunk, nem ügyvédek.
I tried finding some proper English material about this, because my formal Hungarian grammar is very rudimentary, but didn't manage, so here goes. In "X is Y" type of sentences, in the third person plural or singular, using "van" is not allowed (eg.: Ők ügyvédek. A baba okos. Ő sportoló.), but for all other cases it is needed (Én sportoló vagyok, mi sportolók vagyunk, te sportoló vagy). Some other types of sentences may allow for leaving of van: eg.: Hol van az autó? or Hol az autó? are both good, but this doesn't work if there is no a/az: "Hol van Péter?" is good but "Hol Péter?" is not.
Ah, I actually did find something: https://en.wikipedia.org/wiki/Copula_(linguistics)#Zero_copula, this a zero copula case :)