Deca vole ovu igru.

Deca means children and it is plural.

Its singular is dete = child.
So this is an irregular plural:

• dete = child
• deca = children

Even though deca ends in -a, it still takes a plural verb, so you say Deca vole..., not Deca voli...

Vole is the 3rd person plural present tense of voleti = to love.

So:

• ja volim = I love
• ti voliš = you love
• on/ona/ono voli = he/she/it loves
• mi volimo = we love
• vi volite = you love
• oni/one/ona vole = they love

Since deca is plural, the verb must be vole.

Because ovu igru is the direct object of the verb vole.

After voleti in this sentence, the thing being loved goes in the accusative case.

The basic forms are:

• ova igra = this game → nominative
• ovu igru = this game → accusative

So the sentence uses ovu igru because it means this game as the object.

Igru is accusative singular.

Its dictionary form is igra, which is nominative singular.

So:

• igra = game
• igru = game, as a direct object

This is a regular change for many feminine nouns ending in -a:

• žena → ženu
• knjiga → knjigu
• igra → igru

Ovu is the feminine singular accusative form of the demonstrative ovaj = this.

It has to agree with igru in:

• gender: feminine
• number: singular
• case: accusative

So:

• ova igra = this game
• ovu igru = this game (as object)

That is why ovu is correct here.

Here are the basic forms:

• deca → plural noun meaning children; singular is dete
• vole → from voleti
• ovu → from ovaj
• igru → from igra

So if you look words up in a dictionary, you would usually search for:

• dete / deca
• voleti
• ovaj
• igra

No. Serbian word order is fairly flexible because case endings show what each word is doing.

Deca vole ovu igru. is a neutral, natural order: subject + verb + object.

But you can also say:

• Ovu igru deca vole.
• Deca ovu igru vole.

These versions change the focus or emphasis, not the core meaning.

Because Serbian does not have articles like the or a/an.

English says:

• the game
• a game

Serbian usually relies on context or uses words like ovaj/ova/ovo = this when needed.

So:

• igru can mean the game or a game, depending on context
• ovu igru clearly means this game

A simple English-style approximation is:

DEH-tsa VOH-leh OH-voo EE-groo

A few useful sound notes:

• c = ts as in cats
• v is like English v
• g is always hard, as in go
• r is trilled or tapped more than in English

So deca sounds roughly like DEH-tsa.