Learn Hardcore Croatian: Jučer se pokvario lift, ali su ga brzo popravili. - Yesterday the elevator broke, but they fixed it quickly.

So se is essential here; without it, the meaning would change and sound like someone broke the elevator (and the object lift would then normally be in the accusative).

Why is the word order Jučer se pokvario lift and not Jučer se lift pokvario or Lift se jučer pokvario?

All of these are possible, but they have slightly different information focus.

Jučer se pokvario lift.
- Neutral English version: Yesterday the elevator broke down.
- This is quite natural. The time word jučer comes first.
- The verb phrase se pokvario comes before lift, so lift is somewhat new information or emphasized.
Lift se jučer pokvario.
- The subject lift is placed at the beginning, so the speaker is focusing on the elevator (as opposed to something else).
- Roughly: It was the elevator that broke down yesterday.
Jučer se lift pokvario.
- Grammatically possible. Slightly different rhythm; the subject is in the middle.
- se must still be in the second position in the clause, so it stays after jučer.
- This word order is less typical than the sentence given, but still correct.

The key rules:

se must be in the second position in the clause (after the first stressed word).
Word order is flexible and used to express what is old vs. new information or what is emphasized.

Why is the verb pokvario in the masculine singular form?

In Croatian, past tense participles agree with the grammatical gender and number of the subject.

lift is a masculine singular noun.
Therefore, the past participle is pokvario (masc. sg.), not pokvarila (fem. sg.) or pokvarilo (neut. sg.).

Other examples:

Automobil se pokvario. – The car broke down. (masc. sg.)
Mašina se pokvarila. – The machine broke down. (fem. sg.)
Računalo se pokvarilo. – The computer broke down. (neut. sg.)

What tense is pokvario se and how is it formed?

Pokvario se is in the past tense (perfect tense) in Croatian.

Formation:

Auxiliary verb biti (to be) in the present
- past participle of the main verb

Full form would be:

Jučer se je pokvario lift.

However, in standard speech/writing:

The 3rd person singular auxiliary je is normally dropped in sentences where the verb is not at the very end.
So we say: Jučer se pokvario lift.

For they repaired it:

Full: oni su ga popravili
Common: su ga popravili (subject oni is dropped because it’s obvious from context)

Why is the auxiliary su in the middle: ali su ga brzo popravili, not ali popravili su ga brzo?

Croatian has a special rule for clitics (short, unstressed words) like:

su, je, sam (forms of biti in the past tense)
se, ga, je, mi, ti, etc. (short pronouns)

These clitics usually go in second position in the clause.

In ali su ga brzo popravili:

ali = first stressed word of the new clause
therefore, su ga (two clitics) must come right after it.

That gives:

ali su ga brzo popravili
(ali
- clitics su ga
  - rest of the verb phrase)

You can move the adverb brzo or change emphasis, but su ga will always try to stay right after the first major element of the clause:

Jučer su ga brzo popravili.
Brzo su ga popravili.

Why is there no word for they in ali su ga brzo popravili?

Croatian is a pro‑drop language: subject pronouns (ja, ti, on, oni, etc.) are often omitted when the subject is clear from context or from the verb form.

su popravili tells us it’s 3rd person plural (they).
The exact identity (maintenance people, building staff, etc.) is either known from context or not important.

So this:

Oni su ga brzo popravili. – They repaired it quickly.
and this:
Su ga brzo popravili. (with context)
have the same basic meaning, but the explicit oni is usually only used for emphasis or clarity.

What does ga refer to, and why not njega or je?

Ga is the unstressed (short) accusative form of on (he/it, masculine singular).

In this sentence:

ga = the elevator (lift)

Why ga?

lift is masculine singular, and it’s the direct object of popravili in the second clause.
The corresponding clitic pronoun is ga.

Why not njega?

njega is the stressed, long form. You use it for emphasis or contrast:
- Njega su brzo popravili, a drugi lift nisu. – That one they fixed quickly, but not the other elevator.

Why not je?

je = short feminine singular object pronoun (her/it fem.), or 3rd sg. auxiliary.
But lift is masculine, so the right one is ga, not je.

What part of speech is brzo, and can it be placed somewhere else?

Brzo is an adverb meaning quickly, fast.

In ali su ga brzo popravili, it modifies the verb popravili (repaired).

You can move brzo for emphasis, but it usually stays close to the verb:

Ali su ga brzo popravili. – neutral, standard
Ali su ga popravili brzo. – also correct, slight extra emphasis on brzo
Ali brzo su ga popravili. – possible, but sounds a bit marked, focusing on brzo.

The clitics (su, ga, se, etc.) still want to be in second position, regardless of where brzo is.

Why is it pokvario se lift and not se pokvario lift or se lift pokvario?

The rule is that se (a clitic) must appear in the second position in the clause.
Second position means: after the first stressed word of the clause.

In Jučer se pokvario lift:

Jučer is the first stressed word (an adverb).
Therefore se must come after jučer.

So:

Jučer se pokvario lift. – correct
Se jučer pokvario lift. – incorrect (clitic cannot start the sentence)

If you start with Lift:

Lift se jučer pokvario. – here lift is first, se is second: also correct.

You almost never put se in front of the first stressed word; it must come after it.

Could I say Lift je jučer bio pokvaren, ali su ga brzo popravili instead? What’s the difference?

Yes, you can say:

Lift je jučer bio pokvaren, ali su ga brzo popravili.
= The elevator was broken yesterday, but they repaired it quickly.

Differences:

Lift se pokvario jučer
- Focuses on the event of breaking down.
- Answers: What happened yesterday? → It broke down.
Lift je jučer bio pokvaren
- Describes a state: yesterday, the elevator was in a broken condition.
- More like English was broken, rather than broke down.

Both are correct, but pokvario se is more event-like; bio pokvaren is more state-like.

What’s the difference between pokvariti se and kvariti se? And between popraviti and pravljati/popravlja-ti?

Croatian verbs often come in imperfective/perfective pairs.

pokvariti se – perfective
- to break down (once, as a completed event)
- Jučer se pokvario lift. – The elevator broke down yesterday.
kvariti se – imperfective
- to be breaking down, to keep breaking down, to be in the process of going bad
- Lift se stalno kvari. – The elevator keeps breaking down.
popraviti – perfective
- to repair (and finish repairing)
- Brzo su ga popravili. – They repaired it quickly (completed).
popravljati – imperfective (more common than pravljati in this sense)
- to be repairing, to repair repeatedly, to work on repairing
- Sad ga popravljaju. – They are repairing it now.

In your sentence, pokvario se and popravili are perfective because we talk about completed events.

Why is lift in this form? Does it change in other cases?

In the sentence given, lift is in the nominative singular because it’s the subject of the first clause:

Tko se pokvario? – Lift. – Who/what broke down? – The elevator.

In the second clause, the same elevator is referred to by the accusative pronoun ga (direct object), so we don’t repeat lift.

Declension of lift (masculine, inanimate):

Nominative: lift – Lift se pokvario.
Genitive: lifta – nema lifta (there is no elevator)
Dative: liftu – približavam se liftu (I’m approaching the elevator)
Accusative: lift – vidim lift (I see the elevator)
Locative: o liftu – pričamo o liftu (we talk about the elevator)
Instrumental: liftom – idem liftom (I go by elevator)

In your sentence, only the nominative (lift) and the accusative pronoun (ga) are relevant.