Los gorriones pían y revolotean.

Los is the masculine plural definite article, meaning the.

It agrees with gorriones, which is a masculine plural noun:

• el gorrión = the sparrow
• los gorriones = the sparrows

In Spanish, the definite article is also often used for animals or things in a general sense, not only for specific ones. So Los gorriones... can mean either:

• the sparrows in a specific context, or
• sparrows as a kind of animal, depending on context.

The singular is gorrión.

So:

• el gorrión = the sparrow
• los gorriones = the sparrows

A useful thing to notice is that the accent mark changes:

• singular: gorrión
• plural: gorriones

That happens because when the word becomes plural, the normal stress pattern changes, so the written accent is no longer needed.

This is about word stress.

• gorrión ends in -n, so Spanish would normally stress the second-to-last syllable
• but the stress is actually on the last syllable, so it needs a written accent: gorrión

When it becomes plural:

• gorriones ends in -s
• words ending in a vowel, -n, or -s are normally stressed on the second-to-last syllable
• and that is exactly what happens in gorriones

So the accent mark disappears because the pronunciation is now regular.

Both are in the present indicative, third person plural.

They match the subject los gorriones because that subject is plural.

So:

• pían = they chirp
• revolotean = they flutter / they flit about

This is a very common pattern in Spanish:

• singular subject → singular verb
• plural subject → plural verb

For example:

• El gorrión pía = The sparrow chirps
• Los gorriones pían = The sparrows chirp

The accent in pían shows that the í and a are pronounced in separate syllables.

So it is pronounced roughly as:

• pí-an

Without the accent, Spanish readers would normally treat ia as a diphthong and pronounce it as one syllable.

This accent is very common in forms of verbs like piar:

• pío
• pías
• pía
• pían

The written accent helps show both the stress and the fact that the vowels do not merge into one syllable.

Not exactly.

Piar is a specific verb for the sound birds make, especially small birds like sparrows. In English, depending on context, it can be translated as:

• to chirp
• to peep
• sometimes to tweet

Cantar means to sing, and it is much more general.

So in this sentence, pían is more precise than cantan. It specifically evokes the typical small-bird sound.

Revolotean comes from revolotear, which means something like:

• to flutter about
• to flit around
• to fly around in quick, light movements

It does not just mean ordinary flying.

Compared with volar:

• volar = to fly
• revolotear = to flutter around, often in short, restless, light movements

So Los gorriones pían y revolotean gives a lively image: the sparrows are chirping and fluttering around.

Y means and. It simply links the two verbs:

• pían
• revolotean

So the sentence says that the sparrows do both actions.

A useful spelling rule: y changes to e before words that begin with an i sound:

• padre e hijo
• siete e incluso

But here the next word is revolotean, which starts with r, so it stays y.

Because Spanish often does not need subject pronouns.

The verb ending already tells you who the subject is:

• pían
• revolotean

The ending -an shows third person plural, so Spanish speakers do not need to say ellos unless they want extra emphasis or contrast.

So:

• Los gorriones pían y revolotean is normal
• Ellos pían y revolotean would only be used in a context where they needs to be stressed or contrasted

Yes, if the context is already clear.

You could say:

• Pían y revolotean.

That would mean They chirp and flutter about.

Spanish often leaves out subjects when they are already understood from the situation or from earlier sentences. But if you are introducing the idea for the first time, keeping Los gorriones makes the sentence clearer.

A useful approximate pronunciation is go-RRYO-nes.

A few points:

• g before o is a hard g, like in go
• rr is a strong rolled or trilled r
• the stress falls on rri o's o syllable: go-RRIO-nes
• the final s is clearly pronounced in standard Spain Spanish

You do not need a perfect trill immediately, but it is good to notice that r and rr are different sounds in Spanish.