Learn Hardcore German: Wenn das Auto schon wieder kaputtgeht, kriegen wir es hoffentlich schnell repariert. - If the car breaks down yet again, hopefully we will get it repaired quickly.

wenn is used for:
- repeated events (whenever it happens)
- possible/future events (if/when it happens)
als is used for:
- single events in the past (one specific time in the past)

In this sentence, Wenn das Auto schon wieder kaputtgeht talks about a possible future situation (the car might break down again). So wenn is correct.
Als would sound wrong here, because that would suggest you’re talking about one specific time in the past.

Why is the verb kaputtgeht at the end of the wenn-clause?

In German, a subordinate clause (Nebensatz) introduced by words like wenn, weil, dass sends the conjugated verb to the end of the clause.

So:

Main clause: Das Auto geht kaputt.
Subordinate clause: Wenn das Auto kaputtgeht, …

Here geht is the conjugated verb, and kaputt is just an adjective/adverb element that sticks to it. Together they form kaputtgehen, but grammatically geht is the verb, so it moves to the end: … Auto schon wieder kaputtgeht.

Why is kaputtgeht written as one word and not kaputt geht?

The verb is kaputtgehen (to break down, to stop working). It’s a separable verb:

Infinitive: kaputtgehen
Present tense: Das Auto geht kaputt.
Subordinate clause: dass das Auto kaputtgeht

In a subordinate clause, the verb parts come together and form one written unit: kaputtgeht.
So kaputt geht would be wrong here; the correct form is kaputtgeht.

What is the nuance of schon wieder compared to just wieder?

wieder = again (neutral repetition)
- Das Auto geht wieder kaputt. – The car breaks down again.
schon wieder = again, already again with a feeling of annoyance, frustration, or surprise
- Das Auto geht schon wieder kaputt. – The car is breaking down again (ugh, again, seriously?).

So schon wieder adds emotional coloring: the speaker is probably irritated that this is happening yet again.

Why is it present tense geht … kaputt and not a German future tense like wird kaputtgehen?

German often uses the present tense for future events when the context makes the time clear:

Wenn das Auto morgen kaputtgeht, … – If the car breaks down tomorrow, …
Wenn du später kommst, … – If/when you come later, …

Using wird kaputtgehen here would sound heavier and more dramatic, and it’s usually not needed.
So Wenn das Auto schon wieder kaputtgeht, … is the natural way to express a future possibility.

Why does the main clause start with kriegen and not with wir?

Because the wenn-clause comes first, the main clause must start with the conjugated verb to keep the rule that the verb is in position 2:

Basic main clause: Wir kriegen es hoffentlich schnell repariert.
(Position 1 = wir, Position 2 = kriegen)

If you put the wenn-clause at the front, that whole clause counts as position 1:

Wenn das Auto schon wieder kaputtgeht, (position 1)
then the main clause must immediately put the verb in second place:
- kriegen wir es hoffentlich schnell repariert.

So:
Wenn …, kriegen wir … is the correct word order.

What does kriegen mean here, and how is it different from bekommen?

Both kriegen and bekommen can mean to get / to receive.

kriegen is more colloquial / informal.
bekommen is more neutral / standard.

Here:

Wir kriegen es repariert. ≈ We manage to get it repaired / We’ll have it repaired.

A slightly more neutral version would be:

Wir bekommen es hoffentlich schnell repariert.

In everyday spoken German, kriegen is very common and sounds natural in this sentence.

What exactly does wir es hoffentlich schnell repariert kriegen mean as a structure?

This is a common pattern:
etwas (Akk.) + repariert / gemacht / erledigt + kriegen / bekommen

It means something like to manage to get something repaired/done.

Breaking it down:

wir – we
es – it (the car, as a thing to be repaired)
hoffentlich – hopefully
schnell – quickly
repariert – repaired
kriegen – get / manage to

So the structure etwas repariert kriegen = to get something repaired / to manage to have something repaired.

Why is there an es? Could you leave it out?

No, you can’t leave it out here. Es is the direct object of kriegen:

Wir kriegen es repariert. – We manage to get it repaired.

Without es, you’d just have Wir kriegen repariert, which is incomplete and ungrammatical.

Es refers back to das Auto. German keeps the object pronoun here, even though English often drops it in similar constructions (e.g. “We’ll hopefully get it fixed soon” vs. “We’ll hopefully get fixed soon” – the second one changes the meaning).

Why is it repariert and not reparieren?

Here repariert is a past participle, not an infinitive. The pattern is:

etwas repariert kriegen / bekommen
(to get something repaired)

Compare:

Wir lassen das Auto reparieren. – We have the car repaired.
(Infinitive reparieren, with lassen.)
Wir kriegen das Auto repariert. – We manage to get the car repaired.
(Participle repariert, with kriegen.)

The verbs that combine with participles this way include kriegen, bekommen, haben in some constructions:

Wir haben das Auto repariert bekommen.
Ich kriege das nicht erklärt. – I can’t get that explained.

Can I say Wir lassen es hoffentlich schnell reparieren instead? What’s the difference?

Yes, you can say:

Wenn das Auto schon wieder kaputtgeht, lassen wir es hoffentlich schnell reparieren.

Difference in nuance:

Wir lassen es reparieren.
- Focus: we have someone else repair it.
- Neutral, just states that we’ll arrange the repair.
Wir kriegen es repariert.
- Focus: we manage / succeed in getting it repaired.
- Slight nuance of effort or hope that it will work out.

Both are correct; the original with kriegen emphasizes the hope that they will succeed in getting it fixed.

Why is hoffentlich in the middle: wir es hoffentlich schnell repariert kriegen? Could it go somewhere else?

Hoffentlich is a sentence adverb (like hopefully), and it’s fairly flexible in position. Common and natural positions here:

Wir kriegen es hoffentlich schnell repariert.
Hoffentlich kriegen wir es schnell repariert.

Both are fine. Putting hoffentlich right before schnell is very natural: it modifies the whole idea of getting it quickly repaired, not just one single word.
Something like Wir hoffentlich kriegen es schnell repariert would be wrong; the verb must stay in position 2.

Could you use falls instead of wenn here? What would change?

You could say:

Falls das Auto schon wieder kaputtgeht, kriegen wir es hoffentlich schnell repariert.

Difference:

wenn – neutral if/when, often used for conditions and repeated events.
falls – more like in case / if by chance, slightly more hypothetical or formal.

Here, falls would sound a bit more like in case the car happens to break down again.
Wenn is more neutral and typical in everyday speech.

Why is there a comma before kriegen?

German requires a comma between a subordinate clause and the main clause.
Wenn das Auto schon wieder kaputtgeht, is a subordinate clause introduced by wenn, so you must put a comma before the main clause:

Wenn das Auto schon wieder kaputtgeht, kriegen wir es hoffentlich schnell repariert.

This is a strict rule in standard German punctuation.