O filme acaba às oito.

In Portuguese, the present tense is very often used for scheduled future events, especially with times:

• O filme acaba às oito. = The film ends at eight (o’clock).
• This is similar to English: The film ends at eight (present form, but future meaning).
• Acabará is grammatically correct but sounds more formal or literary here and is less common in everyday speech for timetables.

So acaba (present) is the natural, everyday choice.

Acaba comes from the verb acabar (to end, to finish).

• acabar = infinitive (to end)
• ele / ela / você acaba = he / she / you end(s), or it ends

In this sentence:

• O filme = ele (he/it), third person singular
• So we use acaba: O filme acaba… = The film ends…

Às is a contraction of:

• a (preposition: at / to)
• as (feminine plural definite article: the)
  = às

We use às with clock times because horas (hours) is understood:

• às oito (horas) = at eight (o’clock)
  → literally: at the eight (hours)

You cannot say:

• ✗ a oito – wrong for telling the time
• ✗ à oito – wrong: à is a + a (singular), but horas is plural

Correct forms:

• às oito / às oito horas ✅

Because Portuguese is secretly saying “oito horas” (eight hours), which is plural:

• às oito (horas) = at eight o’clock (literally: at the eight hours)
• The noun horas is feminine plural, so:
  • preposition a
  • article as = às

The plural is about hours, not about “eight” itself.

Yes, you can say both:

• O filme acaba às oito.
• O filme acaba às oito horas.

The meaning is the same: The film ends at eight (o’clock).

Às oito horas is just a bit more explicit or slightly more formal / careful speech. In everyday conversation, às oito is very common.

In European Portuguese, you almost always need the definite article with a specific noun:

• O filme = the film
• Filme acaba às oito sounds wrong/unnatural; it feels incomplete, like “Film ends at eight.”

So for a specific movie you’re talking about, you normally say:

• O filme acaba às oito.

(Without o, it might work only in headlines or very telegraphic style.)

Filme is masculine in Portuguese.

• Singular: o filme (the film)
• Plural: os filmes (the films)

Its gender affects:

• The article: o (not a)

• Any adjectives, if present:

  • O filme interessante acaba às oito.
    The interesting film ends at eight.

Here, interessante doesn’t change form, but if you used an adjective that changes with gender/number, it would match filme (masculine singular).

Yes, both are correct and very natural:

• O filme acaba às oito.
• O filme termina às oito.

Nuance:

• acabar = to end, to finish (very common, neutral, everyday)
• terminar = to end, to finish (also common, maybe slightly more formal in some contexts, but both overlap a lot)

In this sentence, they are practically interchangeable.

Yes, that is also correct:

• O filme acaba às oito. (neutral order)
• Às oito, o filme acaba. (time first, then the rest)

Putting Às oito first emphasises the time, but the meaning is the same.
You cannot split it like:

• ✗ O filme às oito acaba. – sounds wrong/very unnatural.

You can specify the part of the day:

• O filme acaba às oito da manhã.
  The film ends at eight in the morning.

• O filme acaba às oito da noite.
  The film ends at eight in the evening / at 8 p.m.

You can also use the 24‑hour clock, especially in more formal or written contexts:

• O filme acaba às vinte horas. = The film ends at 20:00.

But in everyday speech, às oito da noite is very common.

Approximate European Portuguese pronunciation (IPA-style):

• O → [u] (like “oo” in food, but shorter)

• filme → [ˈfiɫ.mɨ]

  • fi like “fee”
  • l is a “dark l”
  • final e is a very short, closed sound [ɨ], like a weak uh

• acaba → [ɐˈka.bɐ]

  • initial a → [ɐ], a very relaxed uh
  • stress on ca: ca = [ka]
  • final a also [ɐ]

• às → [aʃ]

  • like ás in “ash” but the final sound is a sh [ʃ]

• oito → [ˈoj.tu]

  • oi like oy in boy
  • final to like too, but shorter

Together, roughly:
[u ˈfiɫ.mɨ ɐˈka.bɐ aʃ ˈoj.tu]