Djevojčica je našla sivo pero i kaže da je ispalo iz kljuna velike ptice.

Djevojčica means little girl or young girl. It is a diminutive form and sounds clearly childlike.

By contrast:

• djevojka = girl, young woman, or girlfriend depending on context
• djevojčica = specifically a little girl

So Djevojčica je našla... means that the person is a child, not an adult young woman.

Je našla is the Croatian perfect tense, which is the normal past tense in everyday language.

It is made from:

• the auxiliary je = is/has (here functioning as a past auxiliary)
• the past participle našla = found

So:

• našla is the feminine singular form
• it agrees with djevojčica, which is feminine

That is why it is:

• Djevojčica je našla = The girl found

If the subject were masculine, you would get:

• Dječak je našao = The boy found

In Croatian, the past participle agrees with the subject in gender and number.

Here the subject is:

• djevojčica = feminine singular

So the verb must match:

• našla = feminine singular past participle

Compare:

• ona je našla = she found
• on je našao = he found
• ono je našlo = it found

Sivo pero is in the accusative singular, because it is the direct object of našla: the girl found what? — sivo pero.

Both words are neuter singular:

• sivo = grey, neuter singular
• pero = feather, neuter singular

For neuter inanimate nouns, the accusative singular is often the same as the nominative singular, so:

• nominative: sivo pero
• accusative: sivo pero

That is why the form does not visibly change here.

This is very natural in Croatian. The sentence says:

• Djevojčica je našla... = The girl found...
• i kaže... = and says...

Croatian often uses the present tense in narration when reporting what someone is saying at that moment in the story, or to make the narration feel more immediate. In English, we often translate this as:

• The girl found a grey feather and says... or more naturally:
• The girl found a grey feather and says that...
• The girl found a grey feather and is saying that...
• The girl found a grey feather and said that... depending on style and context

So this mixture is not strange in Croatian storytelling.

Here da introduces a subordinate clause, similar to English that.

So:

• kaže da... = says that...

The clause after da is:

• je ispalo iz kljuna velike ptice = it fell out of the beak of a big bird

This use of da is extremely common in Croatian.

This is another perfect-tense form.

Inside the subordinate clause:

• je ispalo = has fallen / fell out

So the sentence contains two separate verb phrases:

1. je našla = found
2. je ispalo = fell out / has fallen out

The second je does not refer back to the first one; it simply belongs to the second verb phrase.

Because the hidden subject of ispalo is pero.

In Croatian, the subject can be omitted when it is clear from context. Here the meaning is:

• kaže da je pero ispalo iz kljuna velike ptice = she says that the feather fell out of the beak of a big bird

Since pero is neuter singular, the past participle must also be neuter singular:

• ispalo

Compare:

• kamen je ispao = the stone fell out (masculine)
• lopta je ispala = the ball fell out (feminine)
• pero je ispalo = the feather fell out (neuter)

Croatian very often leaves out subject pronouns and even repeated nouns when the meaning is clear from context.

English needs:

• she says that it fell out...

Croatian can simply say:

• kaže da je ispalo...

The listener understands that the thing which fell out is the feather mentioned earlier.

This kind of omission is very normal and natural in Croatian.

The verb is ispasti, which often means:

• to fall out
• to drop out
• to come out by falling

Here:

• ispalo iz kljuna = fell out of the beak

It suggests the feather became detached and dropped from the bird’s beak.

Be aware that ispasti can also have other meanings in other contexts, such as:

• to turn out
• to come off badly
• to be eliminated

But here the physical meaning fall out is the correct one.

The preposition iz means out of or from inside, and it requires the genitive case.

The basic noun is:

• kljun = beak

After iz, it becomes:

• iz kljuna = out of the beak

So kljuna is the genitive singular form of kljun.

Velike ptice is also in the genitive singular.

The basic form is:

• velika ptica = a big bird

In this sentence, it means:

• of a big bird

So:

• kljun velike ptice = the beak of a big bird
• iz kljuna velike ptice = out of the beak of a big bird

Both words change because they are in the genitive singular:

• velika → velike
• ptica → ptice

Grammatically, iz directly governs kljuna:

• iz kljuna = out of the beak

Then velike ptice depends on kljuna:

• kljun velike ptice = the beak of a big bird

So the structure is:

• iz
  • kljuna
• kljuna
  • velike ptice

In other words, it is:

• out of [the beak [of a big bird]]

Yes. Croatian word order is more flexible than English word order, although some versions sound more natural than others.

The given sentence:

• Djevojčica je našla sivo pero i kaže da je ispalo iz kljuna velike ptice.

You could also hear variations like:

• Djevojčica je našla sivo pero i kaže da je pero ispalo iz kljuna velike ptice.
• Sivo pero djevojčica je našla i kaže da je ispalo iz kljuna velike ptice.
  This is more marked and gives extra emphasis to sivo pero.

Croatian uses word order not only for grammar, but also for emphasis, rhythm, and style.

Not normally, if you are talking about a bird. Kljun is specifically beak, so it is the natural word here.

• usta = mouth in a general sense
• kljun = beak

Since the sentence says ptica (bird), iz kljuna is the most idiomatic choice.

A rough pronunciation guide is:

• djevojčica ≈ dye-VOY-chee-tsa

A few useful sound notes:

• dj is a soft sound, somewhat like the beginning of duke in some English accents, but not exactly the same
• j is like English y
• č is like ch in church
• c is like ts

So it sounds approximately like:

• dye-VOY-chee-tsa

That is only an approximation, but it is a helpful start for English speakers.