Pielęgniarka myje ranę, zakłada bandaż na nadgarstek i mówi, żebym odpoczął.

Because rana changes to the accusative case here.

• rana = nominative, the basic dictionary form
• ranę = accusative, used because it is the direct object of myje (washes)

So:

• rana = a wound
• myje ranę = washes the wound

This is a very common pattern in Polish: the thing directly affected by the action often goes into the accusative.

Here nadgarstek is also in the accusative: na nadgarstek.

That is because na can take different cases depending on the meaning:

• na + accusative = movement onto / putting onto something
• na + locative = location on something

So:

• zakłada bandaż na nadgarstek = puts a bandage onto the wrist
• bandaż jest na nadgarstku = the bandage is on the wrist

This movement-vs-location distinction is very important in Polish prepositions.

Because Polish often drops subject pronouns when they are clear from context.

In English, you usually need she washes, she puts on, she says.
In Polish, the subject is often understood from:

• the context
• the noun already given: Pielęgniarka
• the verb form

So once you have Pielęgniarka, you do not need to repeat ona.

A less natural version would be:

• Pielęgniarka myje ranę, ona zakłada bandaż...

Polish usually avoids that unless you want contrast or emphasis.

Polish often uses the present tense to describe what is happening in a scene right now, just like English can say:

• The nurse washes the wound, puts on a bandage, and says...

This can sound like a vivid description of an ongoing situation.

Also, these verbs are imperfective, which fits actions viewed as ongoing, repeated, or simply presented without emphasis on completion:

• myć → myje
• zakładać / zakłada (or from zakładać in habitual/present use)
• mówić → mówi

If you changed to perfective verbs, you would usually get a future meaning instead:

• umyje = will wash completely
• założy = will put on
• powie = will say

So the present forms are natural for describing the situation as it unfolds.

Because żebym odpoczął is a subordinate clause, and in Polish such clauses are normally separated by a comma.

So:

• mówi, żebym odpoczął

This is similar to English punctuation in sentences like:

• She says that I should rest.

Words like że, żeby, gdy, kiedy, bo, etc. often introduce clauses that need punctuation.

Żebym is basically żeby + m.

It means something like:

• so that I...
• that I should...
• for me to...

In this sentence:

• mówi, żebym odpoczął
• literally: she says that I should rest

The -m part represents I in this structure.

Related forms are:

• żebym = that I should
• żebyś = that you should
• żeby = that he/she/it should
• żebyśmy = that we should
• żebyście = that you plural should
• żeby = that they should

This is a very common Polish pattern after verbs like:

• mówić = to say
• chcieć = to want
• prosić = to ask
• radzić = to advise

Yes, it looks like past tense, but after żebym it is part of a different construction.

Polish often uses a form built from the past-tense-like l-form after żeby to express something like:

• that I should rest
• for me to rest

So in:

• żebym odpoczął

the meaning is not past. It is more like a wish, recommendation, or instruction.

A very important detail: odpoczął agrees with the speaker/person who is supposed to rest, not with pielęgniarka.

So:

• żebym odpoczął = if the speaker is male
• żebym odpoczęła = if the speaker is female

That is one of the first things English speakers notice, because English does not mark this kind of gender in the same way.

It refers to your gender — the gender of the person who is supposed to rest.

In this sentence, the nurse is speaking, but the clause means:

• that I should rest

So the form matches I, not she.

Examples:

• mówi, żebym odpoczął = she says that I should rest (male speaker)
• mówi, żebym odpoczęła = she says that I should rest (female speaker)

The nurse being female is shown by pielęgniarka, but that does not control the form odpoczął.

Yes, mówi literally means says / is saying / tells, depending on context.

Polish often uses mówi in places where English might prefer:

• says
• tells me
• says that
• says to

So:

• mówi, żebym odpoczął

can naturally correspond to:

• she says that I should rest
• she tells me to rest

If you want to make the indirect object more explicit, you could say:

• mówi mi, żebym odpoczął = she tells me / says to me that I should rest

But leaving out mi is normal when the meaning is already obvious.

Polish word order is fairly flexible, although the given version is very natural and neutral.

The sentence:

• Pielęgniarka myje ranę, zakłada bandaż na nadgarstek i mówi, żebym odpoczął.

is a straightforward narrative order.

But Polish can move things around for emphasis, for example:

• Pielęgniarka myje ranę i zakłada bandaż na nadgarstek, a potem mówi, żebym odpoczął.
• Na nadgarstek pielęgniarka zakłada bandaż...

These alternatives change emphasis or style, but not the core meaning.

For learners, the original order is a good model because it is clear and natural.

Because Polish has no articles.

English distinguishes:

• a bandage
• the bandage

Polish just says:

• bandaż

Context tells you whether it is definite or indefinite.

So:

• zakłada bandaż na nadgarstek

could be understood as:

• puts a bandage on the wrist
• puts the bandage on the wrist

depending on the situation.

This is one of the biggest structural differences between English and Polish.

Yes, it is a natural expression.

The verb zakładać / założyć is often used for putting something on or placing something onto a body part or object:

• zakładać bandaż = put on a bandage
• zakładać okulary = put on glasses
• zakładać rękawiczki = put on gloves

In a medical context, you might also hear other words such as:

• opatrunek = dressing
• zabandażować = to bandage up

But zakłada bandaż is perfectly normal and easy to understand.

Here are the main dictionary forms:

• pielęgniarka = nurse
• myć = to wash
• rana = wound
• zakładać / założyć = to put on, to place on
• bandaż = bandage
• nadgarstek = wrist
• mówić = to speak, say
• odpocząć = to rest

And here are the forms used in the sentence:

• myje from myć
• ranę from rana
• zakłada from zakładać
• mówi from mówić
• żebym odpoczął based on odpocząć

It is very useful in Polish to learn both the dictionary form and the actual form used in the sentence, because endings change a lot.