Ako imate pitanje, Vi ćete razgovarati sa mojom sestrom posle večere.

Capitalized Vi is a polite, formal way to say you in Serbian, especially when addressing one person respectfully.

So:

• vi = you (plural), or informal plural
• Vi = formal singular you

In this sentence, Vi suggests the speaker is talking politely to one person, like a customer, guest, or client.

In modern everyday writing, many people also write vi even in formal contexts, but capital Vi is still common and understood as respectful.

Because in Serbian, after ako (if), the verb is very often in the present tense when talking about a future possibility.

So:

• Ako imate pitanje = literally If you have a question
• but in English the meaning may be future: If you have a question / If you happen to have a question

This is normal Serbian usage. English does something similar:

• If you have time, we’ll talk later.

So the structure is not unusual once you compare it with English.

This is the future tense.

It is made with:

• a form of hteti (will)
• plus the infinitive

Here:

• ćete = you will (plural or formal singular)
• razgovarati = to talk / to speak / to have a conversation

So:

• Vi ćete razgovarati = You will talk

A useful thing to know is that Serbian future can appear in two common ways:

• Vi ćete razgovarati
• Razgovaraćete

Both mean the same thing. With an expressed pronoun like Vi, the split form Vi ćete razgovarati is very natural.

Because that word order is not the normal one.

In Serbian, ćeš, će, ćemo, ćete are clitic forms, and clitics usually want to be in the second position of the clause. That is why:

• Vi ćete razgovarati is natural
• Razgovaraćete is also natural
• Vi razgovaraćete sounds wrong or very unnatural

So once Vi is placed first, ćete comes right after it.

Because the preposition sa (with) requires the instrumental case when it means accompaniment.

The base form is:

• moja sestra = my sister

In the instrumental singular, it becomes:

• mojom sestrom

So:

• sa mojom sestrom = with my sister

This is a very common pattern:

• sa prijateljem = with a friend
• sa profesorkom = with the professor
• sa mojom sestrom = with my sister

Moja is the feminine nominative singular form of my.

But because sestra comes after sa, the noun must be in the instrumental, and the adjective/pronoun describing it must match that case too.

So:

• nominative: moja sestra
• instrumental: mojom sestrom

Both words change because Serbian adjectives and possessives agree with the noun in:

• gender
• number
• case

Because posle (after) requires the genitive case.

The base form is:

• večera = dinner

In the genitive singular, it becomes:

• večere

So:

• posle večere = after dinner

This is the normal pattern with posle:

• posle sastanka = after the meeting
• posle škole = after school
• posle večere = after dinner

Razgovarati sa nekim means to talk with someone / to speak with someone / to have a conversation with someone.

It usually suggests an actual conversation, not just saying a few words.

Examples:

• Razgovaram sa profesorom. = I’m talking with the professor.
• Moramo da razgovaramo. = We need to talk.

In your sentence, it means the person will speak with the speaker’s sister after dinner.

Because the sentence begins with a subordinate clause introduced by ako (if), and in Serbian that clause is separated from the main clause by a comma.

So:

• Ako imate pitanje, Vi ćete razgovarati sa mojom sestrom posle večere.

This is standard punctuation.

It works much like English:

• If you have a question, you will talk to my sister after dinner.

It is understandable and grammatical, especially in a formal context because of Vi.

That said, a native speaker might often say something slightly more natural depending on context, for example:

• Ako imate neko pitanje, razgovaraćete sa mojom sestrom posle večere.
• Ako budete imali pitanje, razgovaraćete sa mojom sestrom posle večere.

Why?

• neko pitanje can sound a bit more natural than bare pitanje in some contexts: if you have any question
• Ako budete imali... can sound a bit more explicitly future-oriented: If you have / happen to have...

But the original sentence is still perfectly understandable and acceptable.

Yes, it could be plural depending on the meaning.

• Ako imate pitanje = If you have a question
• Ako imate pitanja = If you have questions

Both are correct. The singular often means if you have a question / any question, while the plural suggests more than one question or questions in general.

A native speaker might use either one depending on the situation.

Serbian does not have articles like English a/an and the.

So nouns usually appear without an article:

• pitanje = a question / the question
• večera = dinner / the dinner

The exact meaning depends on context.

That is why pitanje by itself can mean:

• a question
• the question
• sometimes even any question, depending on the sentence

Yes. The preposition sa / s both mean with in this kind of sentence.

In practice:

• sa mojom sestrom is completely normal
• s mojom sestrom is also correct

Speakers often use sa because it can be easier to pronounce before certain consonant groups, and it is very common in everyday speech. In this sentence, sa mojom sestrom sounds perfectly natural.