Ona želi ostati još malo u parku.

Yes, Croatian often drops subject pronouns because the verb ending already shows the person and number. So Želi ostati još malo u parku is also completely natural.

Including ona can do things like:

• add emphasis: She wants to stay...
• make the subject clearer in context
• contrast her with someone else

So in this sentence, ona is not required, but it is perfectly correct.

Želi is the 3rd person singular present tense of the verb željeti, meaning to want.

So:

• ja želim = I want
• ti želiš = you want
• on/ona/ono želi = he/she/it wants

In this sentence, ona želi means she wants.

After verbs like željeti (to want), Croatian commonly uses another verb in the infinitive.

So the structure is:

• želi = wants
• ostati = to stay / to remain

Together:

• želi ostati = wants to stay

This is very similar to English want to stay.

This is an aspect question.

• ostati is perfective
• ostajati is imperfective

In many contexts, ostati means to stay / to remain / to end up staying as a complete action or decision.
In this sentence, želi ostati sounds natural because it expresses the intention to stay on.

Ostajati would suggest an ongoing, repeated, or habitual sense, and it would usually not fit as well here.

So:

• Ona želi ostati još malo u parku. = natural
• Ona želi ostajati... = unusual here unless you mean something like she wants to keep staying / to stay regularly

Još malo means a little longer, a bit more, or literally still a little.

Here:

• još = still / more / yet
• malo = little / a little

Together in this sentence, it means she wants to stay for a little while longer.

It is a very common expression in Croatian.

Croatian often uses još malo idiomatically where English would say a little longer.

So even though English uses longer, Croatian naturally says još malo in many situations:

• Pričekaj još malo. = Wait a little longer.
• Ostat ću još malo. = I’ll stay a little longer.

This is just a normal Croatian way of expressing duration in this kind of context.

Parku is in the locative singular.

The noun is:

• park = park

After the preposition u, when you mean in a location, Croatian uses the locative:

• u parku = in the park

So:

• nominative: park
• locative: u parku

Because here u expresses location, not movement.

Croatian uses:

• u + locative = in/at a place
• u + accusative = into a place

Compare:

• Ona je u parku. = She is in the park.
• Ona ide u park. = She is going into/to the park.

In your sentence, she is staying in the park, so it is u parku.

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

The neutral order here is:

• Ona želi ostati još malo u parku.

But other orders are possible, depending on emphasis:

• Želi još malo ostati u parku.
• Još malo želi ostati u parku.
• U parku želi ostati još malo.

These versions can sound slightly different in emphasis, but the basic meaning stays the same. The original sentence sounds natural and neutral.

Yes, you could, but it is not exactly the same in tone.

• želi = wants, wishes, would like
• hoće = wants / is willing / insists on, sometimes stronger or more direct

So:

• Ona želi ostati... sounds more neutral and polite.
• Ona hoće ostati... can sound more forceful, depending on context.

For a simple neutral sentence, želi is usually the better choice.

In this sentence, stay is the most natural English translation.

But ostati can also mean remain, depending on context.

Examples:

• Ona želi ostati još malo u parku. = She wants to stay a little longer in the park.
• Ostao je sam. = He remained alone.
• Ostani ovdje. = Stay here.

So ostati has a range that includes both stay and remain.

It would be:

• Želi ostati još malo u parku.

This is completely correct and very natural. Croatian often omits the subject pronoun when it is obvious from the verb form.

The version with ona is just a bit more explicit or emphatic.

Croatian spelling is quite phonetic, so pronunciation is usually consistent.

• ž is pronounced like the s in measure or the g in genre
• još is pronounced roughly like yosh
• želi sounds roughly like zhe-lee

So:

• želi ≈ zheh-lee
• još malo ≈ yosh mah-lo

The special letter ž is a normal Croatian letter, not just a spelling variation.