Ovo je produžni kabel.

Croatian does not have articles like English a/an and the.

So:

• Ovo je produžni kabel. = This is an extension cable.
• There is no separate word for an.

Croatian usually shows whether something is specific or general through context, not through articles.

That is one of the most common learner questions.

Here, ovo is a standalone demonstrative pronoun meaning this in the sense of this thing here.

In Croatian, when you identify something with This is ..., the language often uses ovo, even if the noun that comes after it is masculine or feminine:

• Ovo je moj brat. = This is my brother.
• Ovo je moja sestra. = This is my sister.
• Ovo je produžni kabel. = This is an extension cable.

But when this directly modifies the noun, then it must agree with the noun:

• ovaj kabel = this cable
• ova knjiga = this book
• ovo dijete = this child

So:

• Ovo je produžni kabel. = This is an extension cable.
• Ovaj produžni kabel = this extension cable

Je means is.

It is the 3rd person singular present form of the verb biti = to be.

So:

• ovo = this
• je = is
• produžni kabel = extension cable

Literally: This is extension cable.

Produžni is an adjective meaning something like extension or extending in this context.

English often uses a noun + noun structure:

• extension cable
• extension cord

Croatian often prefers an adjective + noun structure:

• produžni kabel

So produžni kabel is the normal Croatian way to say extension cable/cord.

Because it has to agree with kabel, which is masculine singular nominative.

Croatian adjectives change their endings to match the noun in:

• gender
• number
• case

Here:

• kabel = masculine singular
• so the adjective is produžni

Compare:

• produžni kabel = masculine
• produžna žica = feminine
• produžno nešto = neuter

So the -i ending is there because the adjective matches kabel.

Yes, kabel is masculine.

A very useful beginner rule is:

• nouns ending in a are often feminine
• nouns ending in a consonant are often masculine
• nouns ending in -o or -e are often neuter

Since kabel ends in a consonant, it is masculine.

This is only a general rule, but it works very often.

It is in the nominative singular.

This sentence is an identification sentence:

• Ovo je X. = This is X.

After je in this type of sentence, Croatian normally uses the nominative:

• Ovo je stol.
• Ovo je knjiga.
• Ovo je produžni kabel.

So both produžni and kabel are in nominative singular.

Yes, but it would mean something slightly different.

• Ovo je produžni kabel. = This is an extension cable.
• ovaj produžni kabel = this extension cable

So:

• Ovo je produžni kabel. is a full sentence.
• Ovaj produžni kabel is just a noun phrase, not a complete sentence by itself.

You could make a full sentence with ovaj:

• Ovaj je kabel produžni.
• Ovaj kabel je produžni.

But those sound more contrastive or marked than the simple neutral sentence Ovo je produžni kabel.

Yes.

Both ovo and to can appear in identification sentences like this, but the nuance is different:

• ovo = this, usually something near the speaker or something being presented
• to = that, or sometimes a more neutral that/it

So:

• Ovo je produžni kabel. = This is an extension cable.
• To je produžni kabel. = That is an extension cable.

In everyday speech, to je... is also very common when referring back to something already mentioned.

Yes. In Croatian, produžni kabel is a normal standard way to refer to what English often calls an extension cable or extension cord.

In everyday speech, people may also shorten it if the context is clear, but produžni kabel is a good standard form to learn.

So even if your English says cord, Croatian will often still use kabel.

A simple English-friendly approximation is:

• produžni ≈ pro-DOOZH-nee
• kabel ≈ KAH-bel

A few pronunciation notes:

• ž sounds like the s in measure or pleasure
• j sounds like English y
• Croatian vowels are usually clear and short: a, e, i, o, u

So produžni has that zh sound in the middle.

Yes, Croatian word order is more flexible than English, but Ovo je produžni kabel. is the most neutral and natural order here.

This order is good for beginners:

• Ovo = topic / thing you are pointing at
• je = is
• produžni kabel = what it is

You may hear different word orders for emphasis, but the standard neutral sentence is:

• Ovo je produžni kabel.

The plural of produžni kabel is:

• produžni kabeli = extension cables

And the full sentence in plural would be:

• Ovo su produžni kabeli. = These are extension cables.

If the demonstrative directly modifies the noun, you would say:

• ovi produžni kabeli = these extension cables

So compare:

• Ovo su produžni kabeli.
• Ovi produžni kabeli