Learn Hardcore Portuguese (Portugal): Se o voo partir amanhã, vais precisar de chegar cedo ao aeroporto. - If the flight leaves tomorrow, you will need to arrive early at the airport.

In Portuguese (Portugal), time-clauses introduced by se (if/when) use the present indicative to talk about future events. The main clause then uses a future tense. So “Se o voo partir amanhã” (literally “If the flight departs tomorrow”) is correct; you don’t say “Se o voo vai partir amanhã.”

What does partir mean in this context? Can’t I use sair?

Partir is the standard verb for a vehicle or transport “departing.” You could understand sair, but it’s more natural to say o voo parte (the flight departs). Sair is more general (“to leave”), but aviation vocabulary prefers partir.

Why is it vais precisar de chegar and not just vais precisar chegar?

In European Portuguese, precisar is normally constructed with de + infinitive:
– precisar de fazer algo (“to need to do something”).
Omitting de is considered incorrect or is a Brazilian influence.

Why does it say vais precisar instead of você vai precisar?

Portugal Portuguese uses the tu form (second-person singular informal) with the verb “vais.” The pronoun tu is dropped because the verb ending -s already marks second person singular.
– tu vais precisar → vais precisar.

Could I use ter de chegar instead of precisar de chegar?

Yes. European Portuguese often says ter de + infinitive for “to have to”:
– vais ter de chegar cedo is perfectly natural and sometimes even more common than precisar de chegar.

Why is it chegar cedo ao aeroporto rather than chegar cedo no aeroporto?

We use a (to) plus the definite article o (the) → ao when expressing movement toward a place:
– chegar ao aeroporto = “arrive at the airport.”
No is contraction of em + o and implies location “in/at,” not movement.

Why is there no article before amanhã?

Amanhã (“tomorrow”) is an adverb of time, so you don’t use an article. You simply say amanhã without o.

Why is the future tense vais precisar used instead of the simple present precisas?

Vais precisar is the near future (periphrasis ir + infinitive) emphasizing that the need will occur.
– Precisas de chegar cedo could also work, but it sounds more like a general advice rather than a future necessity.

What’s the function of Se at the beginning of the sentence?

Se means “if.” It introduces the conditional clause (protasis). The sentence structure is:

Protasis: Se + present → “If the flight departs tomorrow”
Apodosis: future → “you will need to arrive early at the airport.”

Can I swap the order of the clauses?

Yes. You can say:
Vais precisar de chegar cedo ao aeroporto se o voo partir amanhã.
Just keep in mind that if the se-clause comes first, you separate it with a comma; if it comes second, the comma is optional.