Minha irmã quer ir ao cinema, mas meu irmão prefere o museu.

In Portuguese, the possessive word (meu/minha/meus/minhas) agrees with the thing owned, not with the owner.

• irmã (sister) is feminine singular → minha irmã
• irmão (brother) is masculine singular → meu irmão

Basic forms:

• meu – my (masculine singular: meu irmão, meu carro)
• minha – my (feminine singular: minha irmã, minha casa)
• meus – my (masculine plural: meus irmãos)
• minhas – my (feminine plural: minhas irmãs)

quer ir is querer + infinitive, literally “wants to go”:

• quer = “wants”
• ir = “to go”

So:

• Minha irmã quer ir ao cinema = “My sister wants to go to the movies.”

This structure is very common:

• Quero comer. – I want to eat.
• Eles querem viajar. – They want to travel.

You usually cannot say quer ao cinema; querer almost always needs another verb (in the infinitive) or a noun phrase after it.

ao is a contraction:

• a + o = ao

You must contract them; ✗ a o cinema is wrong.

Use ao before masculine singular nouns:

• ir ao cinema – go to the cinema
• ir ao museu – go to the museum

For feminine singular, you usually get à (with accent):

• ir à escola – go to school (a + a = à)

The difference is the verb:

• ir ao cinema – ir (to go) normally takes a preposition indicating direction (a → ao).
• preferir o museu – preferir (to prefer) takes a direct object with no preposition.

So:

• quer ir ao cinema – wants to go to the movies
• prefere o museu – prefers the museum

If you want to keep the same structure with ir, you can say:

• Meu irmão prefere ir ao museu. – My brother prefers to go to the museum.

All three are common, but they are used a bit differently:

• ao cinema = to the cinema (focus on movement toward a place)
• para o cinema = to the cinema (also movement/destination; very frequent in spoken Brazilian Portuguese)
• no cinema = in/at the cinema (location, not movement)

Examples:

• Hoje eu vou ao cinema. – Today I’m going to the movies.
• Hoje eu vou para o cinema. – Same idea, very natural in Brazil.
• Hoje eu estou no cinema. – Today I’m at the movies (already there).

In your sentence, quer ir ao cinema and quer ir para o cinema are both possible; no cinema would sound like “wants to be at the cinema,” not “go to the cinema.”

Both patterns exist, but there is a difference in variety and style:

• In Brazilian Portuguese, it’s very common (and usually more natural) to omit the article with singular close family members:

  • minha irmã, meu irmão, minha mãe, meu pai

• In European Portuguese, you very often see the article:

  • a minha irmã, o meu irmão

In Brazil you can say a minha irmã and o meu irmão, but in everyday speech many people simply say minha irmã, meu irmão as in your sentence.

Yes, you can, and the meaning is almost the same.

• prefere o museu – “prefers the museum” (the place or the idea of visiting it)
• prefere ir ao museu – “prefers to go to the museum” (makes the action explicit)

In context (cinema vs museum), both are understood as a preference between the two activities. The version in your sentence is shorter and completely natural.

All three can express contrast, but they differ in tone and position:

• mas – the most common and neutral “but”:

  • …ao cinema, mas meu irmão prefere o museu.

• porém – more formal/literary, often used after a comma, sometimes in the middle of the sentence:

  • …ao cinema, porém meu irmão prefere o museu.

• só que – very colloquial, like “it’s just that/but” in speech:

  • …ao cinema, só que meu irmão prefere o museu.

In everyday spoken Brazilian Portuguese, mas and só que are much more common than porém.

The tilde (~) over ã and ão marks nasal vowels.

• irmã: roughly eer-MAHN
  
  • final ã is a nasal a (like saying “ah” while letting air go through your nose)
• irmão: roughly eer-MOWN (not exactly English “own”)
  
  • ão is a nasal sound, somewhere between “ow” and “ong,” but nasal.

Other tips:

• The r in irmã/irmão in Brazilian Portuguese is often a soft, breathy sound (similar to the h in English “house”) depending on the region.
• The final m is not fully pronounced; it mostly just makes the vowel nasal.

In Brazilian Portuguese, s between vowels is usually pronounced like z.

In mas meu irmão:

• You say it as one flow: masmeu…
• The s of mas is between the vowel a and the vowel e of meu.
• So it sounds like maz meu.

Compare:

• mas (but) – maz before a vowel
• mais (more) – majs, with an s sound at the end

Yes, they do:

• irmã → irmãs (sisters)
• irmão → irmãos (brothers / siblings)

Patterns:

• many feminine nouns ending in -ã → -ãs in the plural:
  • maçã → maçãs (apple[s])
• many masculine nouns ending in -ão → -ões or -ãos:
  • irmão → irmãos
  • leão → leões (lion[s])

So:

• Minhas irmãs querem ir ao cinema.
• Meus irmãos preferem o museu.

Grammatically, yes; Portuguese allows subject drop because the verb form often shows who the subject is.

However, in your exact sentence it becomes ambiguous:

• mas prefere o museu could mean:
  • she prefers the museum (the sister), or
  • he prefers the museum (the brother), depending on earlier context.

If both irmã and irmão have just been mentioned, it’s clearer to repeat:

• …, mas meu irmão prefere o museu.

If the subject is already crystal clear from context, you can omit it:

• Meu irmão não gosta de cinema. Prefere o museu. – Here it’s clear we’re still talking about my brother.