Dok ona podgrijava juhu, ja režem kruh.

Dok means while in this sentence. It introduces an action happening at the same time as another action.

So:

• Dok ona podgrijava juhu = While she is reheating the soup
• ja režem kruh = I am cutting bread

It connects two simultaneous actions.

Croatian normally uses the present tense for actions happening now, even where English often uses the present continuous.

So:

• podgrijava can mean reheats or is reheating
• režem can mean cut or am cutting

The context tells you that these actions are in progress. Croatian does not need a separate verb form like English am cutting.

Because juha is the direct object of the verb podgrijava. Direct objects often go into the accusative case in Croatian.

• nominative: juha = soup
• accusative: juhu

So podgrijava juhu means she is reheating soup/the soup.

Kruh is also the direct object, but not all masculine nouns change visibly in the accusative.

For many masculine inanimate nouns, the accusative singular is the same as the nominative singular.

So:

• nominative: kruh
• accusative: kruh

That is why you see ja režem kruh.

Yes, in many cases you could leave them out.

Croatian verb endings usually show who is doing the action:

• podgrijava already tells you he/she/it is reheating
• režem already tells you I am cutting

So you could also say:

• Dok podgrijava juhu, režem kruh.

The pronouns ona and ja are included for clarity, emphasis, or contrast. For example, they can help make it clear that she is doing one action and I am doing the other.

The comma separates the subordinate clause introduced by dok from the main clause.

• Dok ona podgrijava juhu, = subordinate clause
• ja režem kruh. = main clause

This is normal punctuation in Croatian, just as in English you would often write:

• While she is reheating the soup, I am cutting bread.

Podgrijava comes from the verb podgrijavati, which means to reheat / to warm up again.

In this sentence:

• podgrijava = she reheats / she is reheating

This is the 3rd person singular present tense form.

A rough breakdown:

• ja podgrijavam = I reheat / am reheating
• ti podgrijavaš = you reheat
• on/ona/ono podgrijava = he/she/it reheats

Režem comes from the infinitive rezati, meaning to cut.

Croatian present-tense forms often do not look exactly like the infinitive, so this is normal.

Here are some present forms:

• ja režem = I cut / I am cutting
• ti režeš = you cut
• on/ona reže = he/she cuts

So the stem changes a little from rez- to rež-/rež- / rež- in the present. This is something learners gradually get used to.

No, not always. Dok can be used in different kinds of sentences, depending on meaning and time reference.

In this sentence, it describes two actions happening at the same time, so the present tense is natural:

• Dok ona podgrijava juhu, ja režem kruh.

But with past contexts, you can also get past forms in the wider sentence. The key idea is that dok links actions that overlap in time.

For a beginner, the most useful thing to remember is:

• in present-time situations, dok often means while
• it commonly introduces a simultaneous action

Yes. Croatian word order is more flexible than English word order.

This sentence could be rearranged in some ways, for example:

• Ja režem kruh dok ona podgrijava juhu.

This still means the same thing. The difference is mainly one of focus and style.

The version you were given starts with the dok clause, which sets the scene first:

• While she is reheating the soup, I am cutting bread.

It can mean either, depending on context.

Croatian does not have a/an/the, so kruh could mean:

• bread
• the bread
• sometimes even a loaf of bread, depending on context

The same applies to juhu:

• soup
• the soup

You understand the exact meaning from the situation, not from an article.

A simple learner-friendly guide:

• podgrijava ≈ pod-gree-YA-va
• juhu ≈ YOO-hoo
• režem ≈ REH-zhem
• kruh ≈ krooh

A few useful notes:

• j in Croatian is like English y in yes
• ž sounds like the s in measure
• h is pronounced, unlike in many English words

So režem is not like English reh-jem, but more like reh-zhem.

It describes ongoing, simultaneous actions.

Both verbs are imperfective in meaning here:

• podgrijava = she is in the process of reheating
• režem = I am in the process of cutting

The sentence presents the two actions as happening at the same time, not as single finished events. That is why it matches English While she is reheating the soup, I am cutting bread so well.