O correio chegou hoje de manhã.

In this sentence, correio means mail/post as a collective idea: letters, packages, and other things delivered by the postal service.

A few related meanings are possible depending on context:

• o correio = the mail / the post
• os Correios = the Brazilian postal service
• o correio can sometimes also refer to the postal system in general

In this sentence, the most natural reading is the mail arrived this morning.

Chegou is the third-person singular form of the verb chegar in the pretérito perfeito (simple past).

It matches o correio, which is singular.

So:

• chegar = to arrive
• eu cheguei = I arrived
• você/ele/ela chegou = you/he/she arrived
• o correio chegou = the mail arrived

This tense is used because the arrival is seen as a completed event.

Because chegou presents the arrival as a single completed action.

• chegou = arrived
• chegava = was arriving / used to arrive / would arrive, depending on context

In this sentence, the speaker is talking about one specific completed event today, so chegou is the natural choice.

If you said O correio chegava hoje de manhã, it would usually need more context and would not sound like the normal way to report a simple completed arrival.

Yes, hoje de manhã is a very common expression meaning this morning.

Literally, it is something like today in the morning, but you should think of it as a set phrase.

Other common time expressions are:

• ontem de manhã = yesterday morning
• amanhã de manhã = tomorrow morning
• hoje à tarde = this afternoon / today in the afternoon
• hoje à noite = tonight / this evening

So even though the literal structure is different from English, the natural translation is this morning.

Yes, but they are not exactly the same in feel.

• hoje de manhã = this morning, very common in everyday speech
• esta manhã = this morning, also correct, sometimes a bit more formal or written depending on context
• pela manhã = in the morning, more general, not necessarily referring to today unless context makes that clear

So in ordinary spoken Brazilian Portuguese, hoje de manhã is extremely natural here.

That word order is very natural in Portuguese. The basic structure is:

• O correio = subject
• chegou = verb
• hoje de manhã = time expression

So the sentence follows a common pattern: subject + verb + time.

You can sometimes move the time expression for emphasis:

• Hoje de manhã, o correio chegou.

That is also correct, but the original sentence is the most neutral and natural.

Here it works more like a collective noun, similar to mail in English. It usually refers to mail in general, not just one specific letter.

If you want to talk about one item, you would normally use a more specific noun, such as:

• a carta = the letter
• a encomenda = the package
• o pacote = the package

So O correio chegou usually means the day’s mail or the postal delivery arrived.

Only when you say where someone or something arrived.

For example:

• O correio chegou hoje de manhã. = The mail arrived this morning.
• O correio chegou à casa às nove. = The mail arrived at the house at nine.
• Cheguei ao trabalho cedo. = I arrived at work early.

So chegar often takes a when followed by a destination, but in your sentence there is no destination, only a time expression, so no preposition is needed after the verb.

Yes, it is correct and natural, especially in contexts where someone is talking about the postal delivery.

That said, in everyday life many Brazilians might also say something more specific depending on what they mean:

• A correspondência chegou hoje de manhã. = The mail/correspondence arrived this morning.
• A encomenda chegou hoje de manhã. = The package arrived this morning.
• O carteiro passou hoje de manhã. = The mail carrier came by this morning.

But O correio chegou hoje de manhã is absolutely understandable and grammatical.

A rough Brazilian Portuguese pronunciation would be:

u ko-REI-u she-GO o-ZHI dji ma-NYÃ

A few helpful notes:

• o often sounds like u in unstressed position
• rr in correio is a guttural h-like sound in Brazilian Portuguese
• chegou has stress on the last syllable: gou
• de manhã has nasal sound in manhã

If you want a slower chunking:

• O correio
• chegou
• hoje de manhã

Normally, no. In standard Portuguese, o artigo is expected here: O correio chegou...

Without o, the sentence sounds incomplete or unusual unless Correio is part of a name, title, or headline style.

So for normal everyday Portuguese, keep o:

• O correio chegou hoje de manhã.

The subject is O correio.

The verb chegou agrees with that subject in the third-person singular.

So the structure is:

• O correio = subject
• chegou = verb
• hoje de manhã = adverbial expression of time

This is a good example of a very common Portuguese sentence pattern.