La pista de audio contiene la locución.

Because Spanish usually does not stack nouns the way English does.

In English, we often say audio track: noun + noun.

In Spanish, that idea is normally expressed with noun + de + noun:

• pista de audio = audio track
• tarjeta de crédito = credit card
• zapatos de deporte = sports shoes

So la pista de audio is the natural Spanish structure.

Pista has several meanings in Spanish, so context matters. It can mean:

• clue
• runway
• track
• court/rink
• and in audio/music contexts, track

Here, in pista de audio, it means track, as in an audio track or sound track.

Contiene is:

• 3rd person singular
• present indicative
• from the verb contener = to contain

So it matches the singular subject la pista de audio:

• La pista de audio contiene... = The audio track contains...

A useful thing to notice: contener is a stem-changing verb in the present tense:

• yo contengo
• tú contienes
• él/ella contiene
• nosotros contenemos
• vosotros contenéis
• ellos contienen

So the e > ie change appears in contiene.

Because both are specific nouns, and Spanish uses articles more often than English.

Here:

• la pista de audio = a specific audio track
• la locución = a specific voice recording / spoken part / locution

Spanish often keeps the definite article where English might drop it or sound more flexible about it.

So this structure is completely normal:

• La pista de audio contiene la locución.

Because de audio describes the type of track, not something belonging to a specific audio file.

Compare:

• pista de audio = audio track / track for audio
• pista del audio = the track of the audio / a track from that audio

So:

• de audio = category or function
• del audio = de + el, meaning of the audio or from the audio

In your sentence, de audio is the normal choice.

Locución can be tricky because it has more than one use.

Common possibilities include:

• spoken recording
• voice-over
• narration
• announcement
• in grammar/linguistics, set phrase or locution

In an audio or media context, it often refers to the spoken voice part of a recording, such as narration, an announcement, or a voice-over.

So even if the translation has already been given, it is worth knowing that locución is a somewhat context-dependent word.

Because in pista de audio, audio is not acting like a regular adjective. It is a noun inside a de phrase.

The main noun is pista, and that is why the article is feminine:

• la pista

The word audio just specifies what kind of track it is:

• de audio

So there is no agreement like you would see with a normal adjective.

Compare:

• la pista sonora → sonora agrees with pista
• la pista de audio → audio stays the same

No. This is standard Spanish word order:

• Subject: La pista de audio
• Verb: contiene
• Object: la locución

So it follows a normal subject + verb + object pattern.

That makes it a very straightforward sentence grammatically.

A Spain Spanish pronunciation would be approximately:

• La pista de audio contiene la locución
• /la ˈpista de ˈawðjo konˈtjene la lokuˈθjon/

A few useful pronunciation points:

• audio begins with au-, like ow in English
• contiene has stress on -tie-
• locución has a written accent, so the stress is on the last syllable: -ción
• In most of Spain, c before i is pronounced like th in thin, so locución sounds like lo-ku-THYON

Because Spanish accent marks show irregular stress.

• locución ends in -n, so without an accent it would normally be stressed on the second-to-last syllable.
• But the actual stress is on the last syllable: lo-cu-CIÓN
• Therefore it needs the written accent: locución

The other words follow normal stress rules, so they do not need an accent mark:

• pista
• audio
• contiene

Yes, in many contexts that would be possible.

Both verbs can work:

• contener = to contain
• incluir = to include

The difference is slight:

• contener can sound a bit more literal or technical
• incluir can sound slightly broader, like one element is part of a set

So La pista de audio contiene la locución is correct, and incluye could also be natural depending on context.