Otwórz bagażnik, proszę.

Otwórz is the singular imperative form of otworzyć.

It is used when speaking to one person and giving a command, request, or instruction: open.

So:

• otworzyć = to open
• otwórz = open! (said to one person)

If you were speaking to more than one person, you would use otwórzcie.

This is mainly about aspect, which is very important in Polish verbs.

• otworzyć is perfective
• otwierać is imperfective

The imperative otwórz usually suggests perform the action and complete it: open it.

The form otwieraj can also mean open, but it often has a slightly different feel, such as:

• focusing on the process,
• repeated action,
• or something like go ahead and be opening it / keep opening it depending on context.

In a simple everyday command like Open the trunk, please, Polish very naturally uses the perfective imperative: Otwórz bagażnik, proszę.

It is in the accusative case, because it is the direct object of the verb otwórz.

You are opening what?
→ bagażnik

However, for a masculine inanimate noun like bagażnik, the accusative singular looks the same as the nominative singular.

So:

• nominative: bagażnik
• accusative: bagażnik

That is why the form does not change here.

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

So bagażnik can mean:

• a trunk
• the trunk

Which one is meant depends on context.

In this sentence, the situation makes it clear that it means the trunk.

Yes, in this sentence proszę means please.

It is a very common polite word in Polish, but it can also have other meanings in other contexts, for example:

• here you go
• go ahead
• yes?
• I ask / I request in more literal uses

In Otwórz bagażnik, proszę, it simply softens the command and makes it polite:

• Open the trunk, please.

It is flexible.

You can say:

• Otwórz bagażnik, proszę.
• Proszę, otwórz bagażnik.
• Otwórz, proszę, bagażnik.

All of these are possible. The most neutral and common version is the one you were given.

The differences are usually about style, rhythm, or emphasis, not basic meaning.

Because in Polish, the verb ending already shows the subject.

Otwórz already means:

• you open!
• more naturally: open! (to one person)

So adding ty is usually unnecessary.

You could say Ty otwórz bagażnik, but that would add emphasis, for example:

• you open the trunk
• maybe contrasting with someone else

Normally, Polish leaves the subject pronoun out.

It is generally polite enough in many everyday situations because of proszę.

Without proszę, Otwórz bagażnik is a straightforward command and can sound more direct.

With proszę, it becomes a polite request:

• Otwórz bagażnik, proszę.

That said, Polish often uses different levels of politeness depending on the situation. If you want to be more formal, especially with a stranger, you might hear:

• Proszę otworzyć bagażnik.

That is a more formal, respectful way to say it.

A very common formal version is:

• Proszę otworzyć bagażnik.

This is used when speaking politely to:

• a stranger,
• an older person,
• someone in a formal situation.

Why not otwórz?
Because otwórz is the imperative used with informal singular you.

In formal Polish, instead of using the plain imperative, people often use:

• proszę + infinitive

So:

• informal: Otwórz bagażnik, proszę.
• formal: Proszę otworzyć bagażnik.

You would use the plural imperative:

• Otwórzcie bagażnik, proszę.

So:

• otwórz = open! (to one person)
• otwórzcie = open! (to more than one person)

If you want to be formal to a group, you can still use:

• Proszę otworzyć bagażnik.

The dictionary form is otworzyć.

This is the infinitive, meaning to open.

A learner may wonder why otwórz looks quite different from otworzyć. That is normal in Polish imperative forms. The stem can change a little.

A useful mini-set is:

• otworzyć = to open
• otworzę = I will open / I open
• otworzysz = you will open / you open
• otwórz = open!

So even though the form changes, it still belongs to the same verb.

A simple approximate pronunciation for an English speaker is:

• ot-voosh ba-GAZH-neek PRO-sheh

A few useful sound notes:

• w in Polish sounds like English v
• ó sounds like oo
• rz here sounds like a sound similar to zh in measure
• ż also sounds like zh
• sz in proszę sounds like sh
• stress is usually on the second-to-last syllable:
  • otwórz
  • bagażnik
  • proszę

The final ę in proszę is often pronounced approximately like e or a nasalized e depending on speech.

Not always.

In this sentence, it clearly means the car trunk or boot.

But bagażnik can also mean other luggage-carrying parts, depending on context, such as:

• a luggage rack
• a bike rack
• a roof rack

So the word is broader than just American English trunk. Context tells you which meaning is intended here.

The word order can change, because Polish word order is more flexible than English word order.

For example:

• Otwórz bagażnik, proszę.
• Proszę, otwórz bagażnik.
• Bagażnik otwórz, proszę.

These versions all mean roughly the same thing, but they can differ in:

• emphasis,
• tone,
• naturalness in context.

The original sentence is a very natural, neutral way to say it.