Learn Hardcore Russian: Мы знакомимся с новыми соседями в нашем доме. - We are getting acquainted with the new neighbors in our building.

The basic meaning of знакомиться is “to get acquainted,” “to meet (for the first time)”.
The ending -ся (or -сь after vowels) is the reflexive marker in Russian. It often means:
- the action is done to oneself (одеваться – to dress oneself), or
- people act on each other (здороваться – to greet each other).

With знакомиться, the idea is “we are becoming acquainted (with each other / with someone).”
So мы знакомимся = we are getting acquainted / we are meeting (for the first time).

Why is it с новыми соседями and not something like новых соседей?

In Russian, many verbs that mean “to meet,” “to become acquainted,” “to communicate” use the preposition + case combination:

с + instrumental case

The verb знакомиться (с кем?) always requires с plus the instrumental case for the person you are getting acquainted with.

новыми соседями is instrumental plural of новые соседи.
Without с, the bare instrumental новыми соседями would sound incomplete here.

So the pattern is:

знакомиться с кем? – с новыми соседями (with new neighbors)
знакомиться с другом (with a friend)
знакомиться с учителем (with the teacher)

What case is новыми соседями, and how are these endings formed?

Новыми соседями is in the instrumental plural.

Nominative plural: новые соседи (new neighbors)
Instrumental plural: новыми соседями (with new neighbors)

Forms:

новыми – instrumental plural of the adjective новый
- masc./neut. nominative singular: новый
- fem. nominative singular: новая
- plural nominative: новые
- plural instrumental: новыми
соседями – instrumental plural of сосед (neighbor)
- singular nominative: сосед
- plural nominative: соседи
- plural instrumental: соседями

So the full pattern is: с + новыми соседями = with new neighbors.

Why does знакомиться use the instrumental case, not the accusative?

Different Russian verbs govern different cases, and this is often idiomatic and must be memorized.

Verbs like знакомиться (с кем?), общаться (с кем?), встречаться (с кем?) use с + instrumental.

Historically, the instrumental case is associated with companionship or “together with”, so:

с новыми соседями = together with new neighbors / in the company of new neighbors

The accusative case would usually express a direct object, but знакомиться doesn’t take a direct object in that way. You don’t “acquaint someone” in Russian; you “get acquainted with someone”, hence с + instrumental.

What is the difference between знакомиться and познакомиться?

They are the imperfective and perfective aspects of the same verb.

знакомиться – imperfective
- Focus on the process, repeated action, or a general situation.
- Мы знакомимся с новыми соседями can mean:
  - we are in the process of getting to know them,
  - or we generally get to know new neighbors (habitually).
познакомиться – perfective
- Focus on the result / one completed event.
- Мы познакомимся с новыми соседями =
  - We will (at some point) meet / get acquainted with the new neighbors.
- Мы познакомились с новыми соседями =
  - We met / got acquainted with the new neighbors (completed in the past).

So aspect changes whether you are talking about an ongoing/general action (знакомиться) or a one-time completed event (познакомиться).

Could I use встречаться instead of знакомиться here?

You can use встречаться, but the meaning changes:

знакомиться с новыми соседями – to get acquainted with new neighbors (first introductions, learning who they are).
встречаться с новыми соседями – to meet / see the new neighbors (have meetings with them, run into them, have regular contact).

So:

Мы знакомимся с новыми соседями – we are in the process of first introductions, getting to know them.
Мы часто встречаемся с новыми соседями – we often meet / run into the new neighbors (maybe already know them).

Why is it в нашем доме and not в наш дом?

The preposition в can take accusative or prepositional, and the choice depends on the meaning:

в + accusative → motion into something (куда? where to?)
- в наш дом – into our house (motion, direction)
в + prepositional → location inside something (где? where?)
- в нашем доме – in our house (static location)

In Мы знакомимся с новыми соседями в нашем доме, the action is happening inside the house, not moving into it, so the prepositional case is used: доме and нашем.

What form is нашем in, and how does it agree with доме?

Нашем is the prepositional masculine/neuter singular form of the possessive pronoun наш (our).

Agreement:

Noun: дом – masculine, singular
- Prepositional: в доме
Pronoun: наш – must match the noun in
- gender: masculine
- number: singular
- case: prepositional

So:

nominative: наш дом (our house)
prepositional: в нашем доме (in our house)

Нашем and доме are both prepositional masculine singular forms.

Is the word order fixed, or can I move parts of the sentence around?

Russian word order is relatively flexible. The neutral, basic order here is:

Мы знакомимся с новыми соседями в нашем доме.

You can rearrange some parts without changing the core meaning, though the emphasis changes:

В нашем доме мы знакомимся с новыми соседями.
– Emphasis on “in our house” (that’s where this is happening).
Мы в нашем доме знакомимся с новыми соседями.
– Slightly marked, but still understandable; focus first on “we in our house” as a setting.

What you generally cannot do is split the preposition from its noun, or the verb from с кем?:

✗ Мы знакомимся с новыми в нашем доме соседями. – sounds wrong/unnatural.

So blocks like с новыми соседями and в нашем доме move as units.

How would the sentence change if it were just one new neighbor instead of several?

You would change the noun and adjective from plural to singular, still in instrumental after с:

Мы знакомимся с новым соседом в нашем доме.

Changes:

новыми соседями (instr. plural) → новым соседом (instr. singular)
Verb знакомимся and the rest of the sentence stay the same.

Patterns:

nominative: новый сосед (a new neighbor)
instrumental: (с) новым соседом (with a new neighbor)

There are no words like “a/the” in Russian. How do we know if this means “new neighbors” or “the new neighbors”?

Russian doesn’t have articles (a, an, the). Whether the meaning feels like “a/some new neighbors” or “the new neighbors” comes from context, not from a specific word.

Мы знакомимся с новыми соседями в нашем доме. could mean:
- We are getting acquainted with some new neighbors in our building, or
- We are getting acquainted with the new neighbors in our building,

depending on what has been mentioned before:

If the neighbors are being mentioned for the first time, English speakers usually translate with “some new neighbors” or just “new neighbors”.
If both the speaker and listener already know which new neighbors are being talked about, English translation naturally uses “the new neighbors.”

Russian leaves this implicit; English adds a/some/the as needed.

How is знакомиться conjugated in the present tense?

Знакомиться is a reflexive verb of the first conjugation. Present tense (imperfective):

я знакомлюсь – I am getting acquainted
ты знакомишься – you (sg., informal) are getting acquainted
он / она / оно знакомится – he / she / it is getting acquainted
мы знакомимся – we are getting acquainted
вы знакомитесь – you (pl. or polite) are getting acquainted
они знакомятся – they are getting acquainted

In the sentence Мы знакомимся с новыми соседями в нашем доме, мы знакомимся is we are getting acquainted.