Ao fazer a reserva, nós perguntamos se a recepção fica aberta durante a noite.

Ao + infinitive is a very common Portuguese structure that means when doing, upon doing, or while doing something.

So:

• ao fazer a reserva = when making the reservation / when we made the reservation

It is formed like this:

• a + o = ao
• followed by an infinitive verb: fazer

A few similar examples:

• Ao chegar, me ligue. = When you arrive, call me.
• Ao entrar, tire os sapatos. = Upon entering, take off your shoes.

In this sentence, ao fazer a reserva sets the time/context for the main action.

Both are possible in Portuguese, but fazer a reserva is a very natural everyday expression.

You can think of these as roughly similar:

• fazer a reserva = to make the reservation
• reservar = to reserve / to book

So Portuguese often uses a verb + noun expression where English might use a single verb.

Examples:

• fazer uma pergunta = to ask a question
• fazer uma compra = to make a purchase
• fazer uma reserva = to make a reservation

A version with reservar would also be possible, such as:

• Ao reservar, nós perguntamos...

But ao fazer a reserva sounds very normal and natural.

Yes. Portuguese often drops subject pronouns when the verb ending already makes the subject clear.

So both of these are correct:

• Nós perguntamos...
• Perguntamos...

Why include nós then?

Usually for one of these reasons:

• emphasis
• clarity
• contrast
• style

Since perguntamos clearly shows we from the ending -amos, the pronoun is not necessary, but it is not wrong at all.

By itself, perguntamos can mean either:

• we ask (present)
• we asked (simple past)

This happens because the nós form of some -ar verbs looks the same in the present and the preterite.

For example:

• nós falamos = we speak or we spoke
• nós perguntamos = we ask or we asked

Context tells you which one is meant. In this sentence, Ao fazer a reserva strongly suggests a past event, so the natural reading is:

• we asked

If someone wanted to make the present meaning clearer, they might say something like:

• Quando fazemos a reserva, perguntamos...

Here se introduces an indirect yes/no question, so it means if or whether.

• perguntamos se... = we asked if / whether...

Examples:

• Ela perguntou se eu estava bem. = She asked if I was okay.
• Não sei se ele vem. = I don’t know whether he is coming.

In this sentence, se does not mean reflexive self, and it is not a conditional if in the sense of if it rains. It means whether.

In this context, recepção usually means the front desk, reception desk, or reception area of a hotel or similar place.

So a recepção fica aberta means:

• the reception/front desk stays open
• the reception is open

A learner should be careful because English reception and Portuguese recepção overlap, but in hotel contexts Portuguese often uses recepção where English might more naturally say front desk.

Both can be possible, but they are slightly different in feel.

• está aberta = is open
• fica aberta = stays open / remains open / is open

In this sentence, fica aberta durante a noite suggests the idea of remaining open during the night, not just being open at one specific moment.

So the sentence is asking about operating hours or continued availability.

Compare:

• A loja está aberta agora. = The store is open now.
• A loja fica aberta até meia-noite. = The store stays open until midnight.

That is why fica aberta sounds very natural here.

Because aberta agrees with a recepção, which is a feminine noun.

• a recepção = feminine singular
• therefore: aberta = feminine singular

Agreement is very important in Portuguese.

Compare:

• o hotel fica aberto = the hotel stays open
• a recepção fica aberta = the reception/front desk stays open

So the ending changes to match the noun it describes.

Yes, à noite is also possible, but the nuance is a little different.

• durante a noite = during the night, emphasizing the whole span of time
• à noite = at night / in the evening-at-night period

In a sentence about whether something remains open through the nighttime hours, durante a noite is especially clear and natural.

Compare:

• A recepção fica aberta durante a noite. = emphasizes being open throughout the night
• A recepção fica aberta à noite. = more generally open at night

Both can work, but durante a noite makes the time coverage more explicit.

Yes. Portuguese allows flexible word order here.

For example:

• Nós perguntamos, ao fazer a reserva, se a recepção fica aberta durante a noite.

This means the same thing. The original version:

• Ao fazer a reserva, nós perguntamos...

sounds very natural because it puts the time/context first, which is common in Portuguese.

So this first phrase works like an introductory time expression.

Very often, yes. Reserva is the standard word for reservation or booking in many contexts, especially hotels, restaurants, flights, and events.

Examples:

• fazer uma reserva no hotel = make a hotel reservation
• confirmar a reserva = confirm the reservation
• cancelar a reserva = cancel the reservation

In travel contexts, Brazilian Portuguese may also use reserva where English speakers often say booking.

Sometimes, but they are not always the same.

• recepção usually refers to the reception/front desk area
• portaria often refers to an entrance/security gatekeeper area, especially in buildings or condos

In a hotel, recepção is usually the better word for reception/front desk.
In an apartment building, portaria might be more natural if you mean the entrance desk/security area.

So in this sentence, recepção is the expected choice if the context is a hotel or inn.

Yes, but that would change the tone or time reference.

The original:

• perguntamos se a recepção fica aberta durante a noite

is very natural when asking about a general policy or normal operating schedule.

Other options:

• perguntamos se a recepção está aberta = asks whether it is open at a certain moment
• perguntamos se a recepção estaria aberta = more tentative/polite, something like would be open

So fica aberta is a strong choice because it focuses on the usual condition over that period of time.