Learn Hardcore Spanish (Latin America): Repito la misma frase en voz alta hasta terminar el capítulo. - I repeat the same phrase out loud until I finish the chapter.

Repito = I repeat/I keep repeating (habit or routine; also neutral statement of what I do).
Estoy repitiendo = I am repeating (right now, in progress). In your sentence, it sounds like a study routine, so repito fits well. If you want to emphasize you’re in the middle of it, use estoy repitiendo.

Why is it hasta terminar and not hasta que termine?

Hasta + infinitive (no que) is used when the subject of both actions is the same. Here, the same “I” repeats and finishes: Repito… hasta terminar….
Hasta que + conjugated verb is used when you change the subject or want a full clause: Repito… hasta que termine el capítulo. Both are correct with the same subject; the infinitive version is a bit lighter stylistically.

If I use hasta que, should it be indicative or subjunctive: hasta que termino or hasta que termine?

Habitual/general statement: indicative. Example: Siempre repito la misma frase hasta que termino el capítulo.
Future/pending action, command, or plan: subjunctive. Example: Hoy voy a repetir la misma frase hasta que termine el capítulo. In the past, you use the past indicative: Ayer repetí… hasta que terminé…

What does en voz alta mean exactly? Can I say en alta voz, a voz alta, or just alto/fuerte?

En voz alta = out loud/aloud. It’s the standard set phrase.
En alta voz is correct but more formal/literary and less common.
A voz alta is not standard.
Alternatives: In Latin America, you often hear hablar/leer fuerte. Hablar alto is common in Spain and understood in Latin America, but fuerte is very natural there. Opposite: en voz baja (in a low voice).

Why frase and not oración for “sentence”?

Both are understood, but:

In Latin America, oración is the standard term for a grammatical “sentence.”
Frase can mean “phrase” or “sentence,” and is very common in Spain; in Latin America it’s fine in everyday speech, but in grammar contexts learners are often taught oración. You could say: Repito la misma oración… if you mean a full sentence.

Can I move en voz alta somewhere else in the sentence?

Yes. Spanish word order is flexible if meaning stays clear:

Repito la misma frase en voz alta hasta… (original)
Repito en voz alta la misma frase hasta…
En voz alta repito la misma frase hasta… (more marked/emphatic) All are correct.

Could/should I use a direct object pronoun, like la?

You can if the noun is known from context:

After mentioning the phrase: La repito en voz alta… Pronoun placement:
Before a conjugated verb: La repito.
Attached to an infinitive/gerund: Voy a repetirla. / Estoy repitiéndola. Don’t double it here: avoid La repito la misma frase (redundant/incorrect in this case).

Why is it la misma frase and not el mismo frase?

Because frase is feminine, so the article and adjective must agree:

la (feminine singular)
misma (feminine singular) Similarly: el mismo capítulo (masculine), las mismas frases (feminine plural).

What’s going on with the verb repetir in repito?

Repetir is a stem‑changing verb (e → i) in the present for all forms except nosotros/vosotros:

yo repito
tú repites
él/ella/usted repite
nosotros repetimos
ustedes/ellos repiten

Why does capítulo have an accent mark?

Stress and spelling rules:

Capítulo is esdrújula (stress on the third‑to‑last syllable: ca‑pí‑tu‑lo). All esdrújulas have a written accent: capítulo.
Repito and terminar follow regular stress rules and don’t need an accent. Note: capitulo (no accent) is a different word form (e.g., “I capitulate” from capitular).

Can I say me repito la misma frase to mean “I repeat the same sentence to myself”?

Yes. Repetir can take an indirect object pronoun for the person receiving the repeated words:

Me repito la misma frase = I repeat the same sentence to myself. You can also be explicit: Me repito la misma frase en voz alta a mí mismo (to myself).

Is terminar el capítulo the only option? What about acabar or terminar con?

Terminar el capítulo and acabar el capítulo are near‑synonyms; both are fine in Latin America.
Terminar con el capítulo can sound like “get it over with” or “be done with it.” It’s understandable, but for neutral “finish reading,” prefer terminar/acabar el capítulo. Don’t confuse with acabar de + infinitive = “to have just done.”

Is there a difference between la misma frase and la frase misma?

Yes:

La misma frase = the same sentence (as before/another one).
La frase misma = the sentence itself (emphasizes the sentence, not something about it). This is a focus/contrast use of mismo after the noun.

What’s the opposite of en voz alta?

En voz baja = in a low voice/quietly. Other options: en silencio (in silence), susurrando (whispering), bajito (very softly, colloquial).

Do I need to say yo repito?

No. Spanish usually drops subject pronouns because the verb ending shows the person. Yo is only added for emphasis or contrast: Yo repito… (as opposed to others).

Could I use para instead of hasta? Like para terminar el capítulo?

Different meanings:

Hasta = until (endpoint in time): Repito… hasta terminar…
Para = in order to (purpose): Repito… para terminar el capítulo means you repeat out loud for the purpose of finishing the chapter. That’s a valid but different idea.

Do I need a comma before hasta?

No comma is needed here. It’s a simple adverbial phrase of time: Repito… hasta terminar el capítulo. You’d use a comma mainly for long, interrupting, or fronted clauses.

Can I say hasta haber terminado el capítulo?

Grammatically yes; it emphasizes the prior completion of finishing relative to the other action. But it’s heavier and less common in everyday speech. The simple hasta terminar el capítulo is more natural.

If another person is the one who finishes the chapter, how do I say it?

Use hasta que with a subject change:

Repito la misma frase en voz alta hasta que él/ella termine el capítulo. You cannot use the infinitive terminar in that case, because hasta + infinitive assumes the same subject as the main verb.

Is there any morphological quirk with voz I should know?

Just pluralization: voz → voces (z → c + es). Example: en voces altas (in loud voices). This doesn’t affect your sentence, but it’s handy to know.