Dječak pokazuje gnijezdo na stablu i pita je li jedno krilo ptice ozlijeđeno.

Dječak is nominative singular, because it is the subject of the sentence: the boy is the one doing the actions.

• dječak = boy
• nominative is the basic dictionary form for a noun when it is the subject

So Dječak pokazuje... means The boy shows/is pointing out...

Because gnijezdo is a neuter singular noun, and for many neuter nouns in Croatian, the nominative and accusative singular are identical.

Here it is the direct object of pokazuje, so it is in the accusative, but the form happens to stay the same:

• nominative: gnijezdo
• accusative: gnijezdo

This is very common with neuter nouns.

Pokazuje is the 3rd person singular present tense of pokazivati.

In this sentence it can mean something like:

• is showing
• points out
• indicates

So Dječak pokazuje gnijezdo... can be understood as The boy is showing/pointing out the nest...

Because Croatian present tense often covers both simple present and present continuous, English may translate it in more than one way depending on context.

Because na stablu expresses location, not movement.

With na, Croatian often uses:

• accusative for movement toward something
• locative for being at/on/in a place

Here the nest is already located there, so Croatian uses the locative:

• stablo = tree, trunk
• na stablu = on/in the tree

So the change is:

• nominative: stablo
• locative singular: stablu

In normal reading, it describes gnijezdo.

So the meaning is:

• the nest on/in the tree

not

• the boy on the tree

Context helps a lot here. Since gnijezdo na stablu is a very natural combination, readers will usually connect na stablu with gnijezdo.

Also, Croatian often uses na stablu or na drvetu where English would more naturally say in the tree.

Je li is a standard way to introduce a yes/no question, and in this sentence it introduces an indirect question after pita.

So:

• pita je li... = asks whether/if...

It is written as two words:

• je
• li

This is the standard spelling.

A learner should be careful not to confuse it with:

• jeli as a common nonstandard spelling
• jesi li contracted in casual speech in some contexts

In standard Croatian here, je li is correct.

Because krilo is a neuter singular noun, and jedan must agree with it in gender, number, and case.

So:

• masculine: jedan
• feminine: jedna
• neuter: jedno

That is why Croatian says jedno krilo.

Ptice is the genitive singular of ptica.

It is used here to show a part-whole or possession relationship:

• krilo ptice = the bird’s wing / the wing of the bird

So:

• nominative: ptica
• genitive singular: ptice

This is very common in Croatian when one noun belongs to or is part of another noun.

Because ozlijeđeno agrees with krilo, which is neuter singular.

The forms are:

• masculine: ozlijeđen
• feminine: ozlijeđena
• neuter: ozlijeđeno

So:

• jedno krilo = neuter singular
• therefore ozlijeđeno must also be neuter singular

Here ozlijeđeno functions like a predicate adjective, meaning injured.

It is best understood here as an adjectival participle used with biti.

In je li jedno krilo ptice ozlijeđeno, the structure is basically:

• je li ... ozlijeđeno = is ... injured

So ozlijeđeno describes the state of the wing, but it comes from the verb ozlijediti.

This is very common in Croatian:

• Vrata su zatvorena = The door is closed
• Ruka je slomljena = The arm is broken
• Krilo je ozlijeđeno = The wing is injured

Yes, Croatian word order is fairly flexible, although this sentence uses a very neutral, natural order.

The given order:

• Dječak pokazuje gnijezdo na stablu i pita je li jedno krilo ptice ozlijeđeno.

is straightforward and standard.

Some parts can move for emphasis, but not all changes sound equally natural. For example, you could move na stablu earlier if you wanted to highlight location. However, je li normally stays near the beginning of its clause.

So for learners, the original order is a very good model to follow.

Yes, and in everyday Croatian na drvetu may even sound more common.

There is a nuance:

• drvo often means tree in everyday speech
• stablo can sound a bit more like trunk or the tree as a plant structure

But in many contexts both are understood, and both can be used for a nest in/on a tree.

So:

• gnijezdo na drvetu = very common everyday phrasing
• gnijezdo na stablu = also understandable, sometimes a bit more specific or formal-looking