Co słychać? Dawno się nie widzieliśmy; odezwij się.

Yes, it is a very common, natural greeting in Polish.

Literally, Co słychać? means something like What is heard?, but in real use it means:

• What’s up?
• How are things?
• What’s new?

It is idiomatic, so it should be learned as a fixed expression rather than translated word for word.

Słychać is an impersonal verb form related to słyszeć (to hear). In expressions like Co słychać?, there is no specific subject such as I, you, or we.

So Polish is not saying What do you hear? but rather something more like:

• What can be heard?
• What’s going on?

This is one reason the phrase sounds unusual if translated literally into English.

It is usually neutral to informal. You can use it with friends, family, classmates, coworkers, and often in casual messages.

For more formal situations, Polish often uses other expressions, for example:

• Jak się masz? – How are you? (can sound a bit textbook or personal depending on context)
• Co u pana/pani słychać? – a more polite version of What’s new?

So Co słychać? is very normal in everyday conversation, especially in friendly contact.

Literally, it means We haven’t seen each other for a long time.

Breakdown:

• dawno = a long time ago / for a long time
• się = here it helps express the reciprocal idea each other
• nie widzieliśmy = we did not see

A more natural English translation is:

• We haven’t seen each other in a long time.
• It’s been a long time since we saw each other.

Here się helps express a reciprocal meaning: each other.

So:

• widzieliśmy = we saw
• widzieliśmy się = we saw each other

This is very common in Polish with actions involving two or more people. Similar examples:

• Znamy się. – We know each other.
• Lubimy się. – We like each other.
• Spotkaliśmy się. – We met / We met each other.

In this sentence, się is necessary.

Polish and English handle this idea differently.

English often uses the present perfect:

• We haven’t seen each other for a long time.

Polish usually uses the past tense with dawno:

• Dawno się nie widzieliśmy.

So even though English uses have not seen, Polish naturally uses a past form here. This is completely normal and should not be translated word for word from English grammar.

The verb is odezwać się, which means:

• to get in touch
• to contact someone
• to say something / speak up (depending on context)

Here odezwij się is the imperative singular, so it means:

• Get in touch.
• Write to me / Call me / Message me.
• Let me hear from you.

In this sentence, the intended meaning is clearly contact me or get in touch.

Yes, odezwać się is a verb normally used with się. In many Polish verbs, się is simply part of the verb as it is commonly used, and it does not always translate directly as oneself.

So you should learn it as a whole unit:

• odezwać się – to get in touch / to speak up
• odezwij się – get in touch

If you leave out się, the phrase would sound wrong.

This is because odezwij się comes from the perfective verb odezwać się, and its imperative form is irregular-looking from an English learner’s perspective.

The important thing is to memorize the pattern:

• infinitive: odezwać się
• imperative singular: odezwij się
• imperative plural / polite: odezwijcie się or niech pan/pani się odezwie

Polish imperatives are not always fully predictable from the infinitive, so this is a good form to learn as a set phrase.

The sentence is addressing one person informally, but Polish usually does not need to state the subject pronoun.

That is because the verb form already shows the person:

• odezwij się = imperative to one person, informal (you singular)

So Polish often omits pronouns like ty (you) unless they are needed for emphasis.

For more than one person informally:

• Co słychać? Dawno się nie widzieliśmy; odezwijcie się.

For one person formally:

• Co słychać? Dawno się nie widzieliśmy; niech pan/pani się odezwie.

A more natural fully polite version might also rephrase the first part, for example:

• Co u pana/pani słychać? Dawno się nie widzieliśmy; proszę się odezwać.

So the original sentence is clearly informal and aimed at one person.

Yes. The semicolon links two closely related ideas:

• We haven’t seen each other in a long time
• Get in touch

It gives a slightly more deliberate written style than a comma. In casual writing, people might also use:

• Dawno się nie widzieliśmy, odezwij się.
• Dawno się nie widzieliśmy. Odezwij się.

All three are understandable. The semicolon is correct and stylistically neat, but it is not the only possible punctuation.

A simple pronunciation guide:

• Co słychać? ≈ tso SWI-hahkh
• Dawno się nie widzieliśmy ≈ DAV-no sheng nye vee-dzye-LI-shmi
• odezwij się ≈ o-DEZ-veey sheng

A few useful notes:

• ł sounds like English w
• cz / ć / ci-type sounds can be tricky; chać is softer than plain English chat
• się is often pronounced approximately like sheng in everyday speech
• stress is usually on the second-to-last syllable:
  • słyCHAĆ
  • widzieLIśmy
  • oDEzwij

A learner does not need perfect phonetics at first, but getting ł, się, and the general stress pattern right helps a lot.