Eu quero apresentar minha esposa aos meus amigos no domingo.

Because after quero (I want), Portuguese uses the infinitive form of the next verb.

• quero apresentar = I want to introduce
• apresento means I introduce / I am introducing

So:

• Eu quero apresentar minha esposa... = I want to introduce my wife...

This works like:

• Eu quero comer = I want to eat
• Eu quero sair = I want to leave

Yes. Very often, Portuguese drops the subject pronoun when it is clear from the verb.

So both are natural:

• Eu quero apresentar minha esposa aos meus amigos no domingo.
• Quero apresentar minha esposa aos meus amigos no domingo.

Both mean the same thing. Brazilian Portuguese often includes pronouns for emphasis or clarity, but omitting eu is completely normal here.

Because esposa is a feminine noun, so the possessive has to agree with it.

• minha esposa = my wife
• meu marido = my husband

Agreement examples:

• meu amigo = my friend (male)
• minha amiga = my friend (female)
• meus amigos = my friends
• minhas amigas = my friends

So the possessive changes to match the noun’s gender and number.

Because the verb apresentar often uses the pattern:

• apresentar alguém a alguém
• to introduce someone to someone

In your sentence:

• minha esposa = the person being introduced
• aos meus amigos = to my friends

The a comes from the verb pattern, and os is the plural masculine article the. These combine:

• a + os = aos

So:

• aos meus amigos = to my friends

Aos is a contraction of:

• a
  • os = aos

Here:

• a = the preposition to
• os = the (plural masculine)

Other common contractions:

• a + o = ao
• a + a = à
• a + as = às

Examples:

• ao professor = to the teacher
• à professora = to the teacher
• aos amigos = to the friends
• às amigas = to the friends

Good question. In Portuguese, possessives can appear with or without an article, depending on the structure and style.

With family members or close relationships, Brazilian Portuguese often allows:

• minha esposa
• a minha esposa

Both can be correct.

But in aos meus amigos, the article is part of the contracted form created by the preposition:

• a + os meus amigos = aos meus amigos

So here the article naturally appears inside the contraction.

In short:

• minha esposa: article is optional in many contexts
• aos meus amigos: the article is built into the structure

Yes, but only if the grammar calls for a + a.

For example:

• Vou apresentar isto à minha esposa.
• I’m going to present/show this to my wife.

Here:

• a = to
• a minha esposa = my wife

So:

• a + a = à

But your original sentence is different:

• apresentar minha esposa aos meus amigos
• introduce my wife to my friends

Here minha esposa is the direct object, not the person receiving the introduction.

Not always. Apresentar can mean several related things, depending on context, such as:

• to introduce
• to present
• to show
• to submit

Examples:

• Quero apresentar minha esposa aos meus amigos.
  = I want to introduce my wife to my friends.

• Vou apresentar o projeto amanhã.
  = I’m going to present the project tomorrow.

So the meaning depends on what follows and the situation.

Because no is the contraction of:

• em + o = no

In time expressions, Portuguese often uses em where English uses on.

So:

• no domingo = on Sunday

Related forms:

• na segunda-feira = on Monday
• no sábado = on Saturday
• no fim de semana = on the weekend

This is very common and natural.

Sometimes yes, but the meaning or feel can change a little.

• no domingo = on Sunday
• domingo can sound more like Sunday as a time reference without the preposition, depending on context

For example:

• Vou viajar domingo.
• Vou viajar no domingo.

Both can be heard in Brazilian Portuguese, and both can mean I’m going to travel on Sunday.
But no domingo is especially clear and standard in many contexts.

In your sentence, no domingo is perfectly natural and clear.

Because the sentence is talking about:

• one wife = minha esposa
• more than one friend = meus amigos

Each noun and its possessive agree separately:

• minha esposa = singular feminine
• meus amigos = plural masculine

So the sentence is grammatically balanced:

• minha matches esposa
• meus matches amigos

Yes. If the group is entirely female, you would say:

• Eu quero apresentar minha esposa às minhas amigas no domingo.

Changes:

• aos becomes às because:
  • a + as = às
• meus amigos becomes minhas amigas

So:

• aos meus amigos = to my male/mixed friends
• às minhas amigas = to my female friends

If the group is mixed or unspecified, amigos is the normal default plural.

The original order is very natural:

• Eu quero apresentar minha esposa aos meus amigos no domingo.

But Portuguese allows some flexibility. For example:

• No domingo, eu quero apresentar minha esposa aos meus amigos.
• Eu quero, no domingo, apresentar minha esposa aos meus amigos.

The first alternative is especially common if you want to emphasize the time.

Still, your original version is the most straightforward and neutral.

Your sentence already sounds natural. A very common everyday version would be:

• Quero apresentar minha esposa pros meus amigos no domingo.

Here:

• pros = spoken/written informal contraction of para os
• pros meus amigos = to my friends

This is very common in speech.
But your original sentence with aos meus amigos is correct, clear, and slightly more formal or careful.

So both are good:

• Quero apresentar minha esposa aos meus amigos no domingo.
  More standard/formal

• Quero apresentar minha esposa pros meus amigos no domingo.
  More conversational