"tendremos" in flash card, 'correct' answer: "have". (is this the right place for this kind of reports?)
The flashcards are notoriously imprecise. I'm not sure where to report oddities, but people have been doing so in the forums. (Though whether those reports are successful, I cannot say.)
Anyway, "tendremos" is a correct conjugation of "tener," it's "we will have."
Actually those errors are a good thing: Now I must think myself and not solely memorize! :D