Mam wrażenie, że ten nowy sąsiad zna już wszystkich na naszym osiedlu.

Mam wrażenie literally means I have the impression. In natural English, the whole phrase Mam wrażenie, że... is often translated as:

• I have the impression that...
• It seems to me that...
• I get the feeling that...

It introduces a personal impression, not a hard fact.

Że means that and introduces a subordinate clause.

So:

• Mam wrażenie = I have the impression
• że ten nowy sąsiad zna już wszystkich... = that this new neighbor already knows everyone...

This is very common in Polish. After verbs and expressions like myślę (I think), wiem (I know), wydaje mi się (it seems to me), or mam wrażenie (I have the impression), you often get że.

Ten means this or that, depending on context. Here ten nowy sąsiad means this new neighbor.

In Polish, ten is a demonstrative pronoun. It can point someone out more specifically, a bit like:

• this new neighbor
• that new neighbor

Sometimes in everyday Polish, words like ten / ta / to are used more often than this/that would be in English, so they can sound a little less strongly demonstrative than a direct English translation suggests.

Polish uses different verbs for different kinds of know.

• znać = to know a person, place, work, topic; to be familiar with
• wiedzieć = to know a fact or piece of information

So:

• zna sąsiadów / zna wszystkich = he knows the neighbors / he knows everyone
• wie, gdzie mieszkają = he knows where they live

Here the object is people, so zna is the correct choice.

Not in the same way.

• zna wszystkich = he knows everyone (state/result)
• poznał wszystkich = he met/got to know everyone (completed action)

So zna już wszystkich means that by now he is already acquainted with everyone.
If you said poznał już wszystkich, you would be focusing on the action of meeting/getting to know them.

Because znać takes a direct object, and that object must be in the accusative case.

• wszyscy = nominative, used for a subject: Everyone knows him
• wszystkich = accusative form here, used for the object: He knows everyone

So in this sentence:

• ten nowy sąsiad = subject
• zna wszystkich = verb + object

Because for masculine personal plural, the accusative often has the same form as the genitive.

That is why you get:

• nominative: wszyscy
• accusative/genitive: wszystkich

Since everyone here means all the people, Polish uses the masculine-personal plural pattern. This is normal even when the group is mixed or unspecified.

Here it means everyone or all the people.

More literally, the sentence suggests:
this new neighbor already knows all the people on our estate/in our neighborhood.

Polish often uses wszystkich in this way when the people being referred to are understood from context.

Because na is used here in the sense of on/in a place such as a housing estate or residential area, and after na expressing location, Polish uses the locative case.

So:

• osiedle = base form
• na osiedlu = on/in the estate
• na naszym osiedlu = on/in our estate

Also notice agreement:

• naszym matches osiedlu
• both are locative singular neuter

Osiedle usually means a housing estate, residential development, or sometimes roughly neighborhood/residential area.

There is not always one perfect English equivalent. Depending on context, it could suggest:

• a block/apartment complex area
• a planned residential estate
• the local neighborhood where people live

So na naszym osiedlu may be translated naturally as in our neighborhood even though the Polish word is more specific than that.

Już means already, and Polish word order is more flexible than English word order.

In this sentence:

• zna już wszystkich = already knows everyone

This is very natural. You could also hear:

• już zna wszystkich

Both are correct, but the placement can slightly change what is emphasized.

• zna już wszystkich can emphasize the surprising extent: he knows everyone already
• już zna wszystkich can emphasize the fact that already he knows them

The meaning stays very close.

No, not completely. Polish allows more flexibility than English because case endings show grammatical roles.

The neutral version here is:

• Mam wrażenie, że ten nowy sąsiad zna już wszystkich na naszym osiedlu.

But you might also hear variations such as:

• Mam wrażenie, że ten nowy sąsiad już zna wszystkich na naszym osiedlu.
• Mam wrażenie, że na naszym osiedlu ten nowy sąsiad zna już wszystkich.

These versions shift emphasis, but the core meaning stays the same.