O reboque chegou agora.

O is the masculine singular definite article, equivalent to the in English.

So o reboque = the tow truck / the trailer / the towing vehicle, depending on the meaning already given in context.

It tells you this is a specific, identifiable thing, not just any one.

• O reboque chegou agora. = The reboque arrived just now.
• Um reboque chegou agora. = A reboque arrived just now.

Because reboque is a masculine noun in Portuguese.

That means it normally takes masculine articles and adjectives:

• o reboque
• um reboque
• esse reboque

This grammatical gender is a property of the noun. It does not necessarily mean anything biological.

Chegou is the 3rd person singular of chegar in the preterite (simple past).

So it means arrived or, depending on context, has arrived.

Breakdown:

• infinitive: chegar = to arrive
• preterite: chegou = arrived

Because the subject is o reboque, which is singular, the verb is also singular.

Portuguese often uses the preterite where English might naturally use either:

• arrived
• has arrived
• just arrived

So O reboque chegou agora can sound very natural in Portuguese even if the best English translation is something like The tow truck has just arrived.

This is a very common difference between English and Portuguese. Portuguese does not match the English present perfect in a one-to-one way.

Here, agora most naturally means just now.

With a past verb like chegou, agora often refers to something that happened very recently:

• chegou agora = arrived just now

In other contexts, agora can also mean:

• now
• right now
• at the moment

So the exact shade depends on the verb tense and the situation.

You can say está chegando agora, but it means something slightly different.

• chegou agora = the arrival is already completed
• está chegando agora = the arrival is happening right now / is in progress

So if the vehicle has already arrived, chegou agora is the better choice.

Yes, but the emphasis changes.

The most neutral order is:

• O reboque chegou agora.

If you say:

• Agora o reboque chegou.

you are usually putting extra emphasis on agora, often with a contrastive feeling, something like:

• Now the tow truck has arrived
• The tow truck has finally arrived now

So both are possible, but the original sentence is the most straightforward and neutral.

Because the subject is already stated: o reboque.

Portuguese does not need an extra pronoun when the noun is already there.

• O reboque chegou agora. = natural
• Ele chegou agora. = natural only if the context already makes clear that ele refers to o reboque
• Ele o reboque chegou agora. = not natural in normal Portuguese

So once the noun is present, a separate pronoun is usually unnecessary.

Not in this sentence, because no destination is mentioned.

Here the sentence only says that the reboque arrived, not where it arrived.

If you add a place, then a preposition may appear:

• O reboque chegou ao local. = The tow truck arrived at the location.
• O reboque chegou em casa. = The tow truck arrived at home.

So in O reboque chegou agora, no preposition is needed.

A rough Brazilian pronunciation is:

u heh-BO-ki sheh-GOH a-GO-ra

A few helpful notes:

• o as an unstressed article often sounds like u
• the r at the start of reboque is often pronounced like an English h in many Brazilian accents
• ch in chegou sounds like sh
• final ou in chegou sounds like ohw / oh

A more technical approximation is:

/u ʁeˈbɔki ʃeˈgow aˈɡɔɾa/

Pronunciation varies by region, but this will help you sound close to standard Brazilian speech.

Yes. Depending on context, reboque can refer to things related to towing or a trailer.

That is why context matters. In one situation it may mean something like:

• tow truck
• trailer
• towed vehicle

So even if you already know the intended meaning in this sentence, it is useful to remember that reboque is not always limited to just one English word.