La sucursal de correos cierra a las seis.

Sucursal means branch or branch office.

So la sucursal de correos is not just any post office in general; it specifically suggests a branch of the postal service.

A few related words:

• sucursal = branch
• oficina = office
• oficina de correos = post office
• correo / correos = mail, postal service, or post office depending on context

In this sentence, de correos is a normal way to say of the postal service or post office branch.

Why not del correo?

• del = de + el
• But here Spanish commonly uses correos as the name of the service or institution, without el

So sucursal de correos is a set phrase in many contexts, similar to:

• oficina de correos = post office
• servicio de correos = postal service

Also, correo in the singular often means mail or even email, so de correos helps make the institutional meaning clearer.

They are very close, but not exactly identical.

• la oficina de correos = the post office
• la sucursal de correos = the post office branch / postal branch office

So sucursal emphasizes that it is one branch location of a larger organization.

In everyday speech, many people would simply say la oficina de correos or even el correo, depending on the country.

Because the subject is la sucursal, which is singular.

Breakdown:

• La sucursal de correos = the post office branch
• cierra = closes

Even though correos is plural, it is not the subject. It is just part of the phrase de correos describing sucursal.

So the verb agrees with sucursal, not with correos.

Spanish often leaves out subject pronouns when they are not needed.

In English, you say:

• It closes at six.

In Spanish, once the subject is stated, you usually do not add a pronoun:

• La sucursal de correos cierra a las seis.

You could say ella cierra, but that would sound unnatural here unless you were emphasizing the subject for some special reason.

Spanish uses a before clock times with most verbs.

So:

• cierra a las seis = closes at six
• abre a las nueve = opens at nine
• llego a las ocho = I arrive at eight

This is just the standard way to express at with a specific time.

One important exception is with the verb ser when telling time:

• Son las seis. = It’s six o’clock.

But with actions happening at a time, use a:

• Cierra a las seis.

Because for most hours, Spanish uses the plural article:

• a las dos
• a las cinco
• a las seis

The only common exception is one o’clock:

• a la una

Why? Because Spanish treats the hours as:

• la una = one (singular)
• las dos, las tres, las seis = plural

So:

• Cierra a la una.
• Cierra a las seis.

Usually it means at six.

So:

• La sucursal de correos cierra a las seis = The post office branch closes at six.

In normal use, this means six o’clock is the closing time.

English sometimes uses by six a little differently, but Spanish a las seis points to the specific time itself.

Because the infinitive is cerrar and it is a stem-changing verb.

In the present tense, e changes to ie in many forms:

• yo cierro
• tú cierras
• él/ella/usted cierra
• nosotros cerramos
• ellos cierran

So cierra is the correct él/ella/usted form.

This is why you see:

• La tienda cierra temprano.
• La puerta cierra mal.

Not cerra.

The infinitive is cerrar, meaning to close.

Here is the present tense:

• yo cierro
• tú cierras
• él/ella/usted cierra
• nosotros/nosotras cerramos
• ellos/ellas/ustedes cierran

In this sentence, cierra matches the singular subject la sucursal.

Yes.

Spanish cerrar can be:

• transitive: to close something
  
  • Cierro la puerta. = I close the door.
• intransitive: to close / to shut / to stop operating
  
  • La tienda cierra a las ocho. = The store closes at eight.

In your sentence, it is being used intransitively:

• La sucursal de correos cierra a las seis.

Not exactly.

Although correos is literally plural, in phrases like oficina de correos or sucursal de correos, it often refers to the postal service or post office system as an institution.

So here it is not really about counting individual letters. It is more like a fixed expression.

That said:

• correo can mean mail, post, or email
• correos can also appear in other contexts as a plural noun, depending on usage

But in this sentence, it is best understood as part of the standard postal-service expression.

In many places, yes, people do say el correo to mean the post office.

However, usage varies by country. In Latin America:

• correo can mean mail
• el correo can mean the post office
• oficina de correos is often clearer
• sucursal de correos sounds more specific, like a branch location

So El correo cierra a las seis may be understood, but La sucursal de correos cierra a las seis is more explicit.

A simple pronunciation guide is:

cierra ≈ SYEH-rra

A few details:

• cie- sounds like syeh in most of Latin America
• the rr is a rolled or trilled r
• stress falls on the first syllable: CIE-rra

So the whole sentence is roughly:

La su-cur-sal de co-rre-os SYEH-rra a las seis.

Because in Spanish, after de, a noun often appears without an article when it functions like a category or type.

For example:

• tienda de ropa = clothing store
• vaso de agua = glass of water
• oficina de correos = post office

So de correos works like postal / of the postal service, and it does not need los here.

If you said de los correos, it would usually sound like you were referring to some specific set of mails or postal services, which is not the intended meaning.

Yes.

Spanish commonly uses the present tense for schedules, routines, and fixed times:

• La tienda abre a las nueve.
• El banco cierra a las cuatro.
• La sucursal de correos cierra a las seis.

This is just like English, which also often uses the simple present for schedules:

• The branch closes at six.

Usually it means the general closing time or a scheduled fact: it closes at six.

If you want to strongly emphasize a one-time event happening today, Spanish often uses other wording, such as:

• Hoy cierra a las seis. = Today it closes at six.
• Va a cerrar a las seis. = It’s going to close at six.

But without extra context, the plain sentence sounds like a normal statement of business hours.

You would say:

La sucursal de correos cierra a la una.

Notice the change:

• a la una
• but a las dos / a las seis / a las ocho

This is one of the most common time-expression patterns in Spanish.

Yes. Spanish word order is flexible.

These are all possible:

• La sucursal de correos cierra a las seis.
• A las seis cierra la sucursal de correos.
• La sucursal de correos, a las seis, cierra. (less natural in everyday speech)

The most neutral and natural version is the original:

• La sucursal de correos cierra a las seis.

Yes. If the subject were plural, the verb would become plural too:

• Las sucursales de correos cierran a las seis. = The post office branches close at six.

If you were addressing people directly, Latin American Spanish generally uses ustedes rather than vosotros:

• Ustedes cierran a las seis. = You all close at six.

But in your original sentence, the subject is not you, so this does not affect the form.

Because the phrase a las + number strongly signals a clock time.

So:

• a las seis = at six o’clock

Without that structure, seis is just the number six.
But with a las, it is clearly a time expression.