Breakdown of Avremo perso i biglietti. Dovremo aspettare.
il biglietto
the ticket
avere
to have
aspettare
to wait / to wait for
dovere
must
Questions & Answers about Avremo perso i biglietti. Dovremo aspettare.
Why is avremo perso translated as "must have lost" rather than "will have lost"?
This is a great example of the "epistemic future" or futuro epistemico. In Italian, the future tenses are often used to express a guess, a deduction, or probability rather than an actual future event. Because losing the tickets is something that already happened, we use the future perfect (avremo perso) to express a guess about the past, meaning "we probably lost" or "we must have lost" them.
Is dovremo in the second sentence also being used to make a guess?
No, in this case, dovremo is functioning as a standard future tense. It describes the literal future consequence of losing the tickets: we will have to wait. This sentence nicely contrasts the two uses: the first uses the future to guess about the past, while the second uses it to state a future fact.
How exactly is the tense for avremo perso formed?
It is the future perfect, or futuro anteriore. You form it by taking the standard future tense of your helper verb (avere or essere)—in this case, avremo for "we will have"—and adding the past participle of your main verb, which is perso from perdere.
Since English says "We must have lost...", could I use the verb dovere in Italian here instead?