Learn Hardcore Croatian: Skreni lijevo kod škole, pa idi ravno. - Turn left by the school, then go straight.

Skreni and idi are 2nd‑person singular imperatives (informal; to one person you know or are speaking to casually).
Use Skrenite, idite for plural or to be polite/formal with one person.
To soften, add Molim te (informal) or Molim vas (polite): Molim vas, skrenite lijevo kod škole, pa idite ravno.

Why is it kod škole and not u školi or na školi? What case is škole?

kod means “at/by/near” a landmark or someone’s place and governs the genitive case. škole is genitive singular of škola.
u školi = “in the school” (inside); na školi would literally be “on the school” (on top of the building), so not used for directions.
Close spatial alternatives:
- pored/pokraj škole = next to the school,
- uz školu = alongside the school,
- do škole = up to/as far as the school (endpoint, not location).

Is the comma before pa necessary?

In standard Croatian, a comma is generally not used before coordinating pa. So the neutral punctuation is: Skreni lijevo kod škole pa idi ravno.
Writers sometimes insert a comma to mark a pause; you’ll see it in informal text. In careful writing, omit it.

What does pa mean here? Can I use onda or zatim?

Here pa links actions in sequence: “and then / so”.
onda and zatim both mean “then/after that”; they’re a bit more explicit or formal. All work: ..., pa idi ravno / ..., onda idi ravno / ..., zatim idi ravno.

Why is it perfective skreni but imperfective idi? Is that mix normal?

Yes. Commands often use:
- a perfective for a single, bounded action: skrenuti → skreni (“make the turn once”), and
- an imperfective for an ongoing action: ići → idi (“keep going”).
You could also say nastavi ravno (“continue straight”), another imperfective.

Can I say Skreni na lijevo or Skreni u lijevo?

The idiomatic form for directions is simply Skreni lijevo (adverb).
na lijevo appears in drill/marching commands (Okreni se na lijevo!), not in everyday navigation.
u lijevo is not idiomatic here.

What’s the difference between lijevo, levo, and ljevo?

lijevo is standard Croatian (ijekavian).
levo is standard in Serbian (ekavian); widely understood.
ljevo is a common colloquial form in parts of Croatia but is nonstandard in the written language.

Is idi ravno the only way to say “go straight”? What about idi pravo or word order like Ravno idi?

Both idi ravno and idi pravo mean “go straight”. In Croatia, ravno is more common; pravo is very common in Bosnia/Serbia and also understood in Croatia.
You can also use nastavi ravno (“continue straight”).
Ravno idi is possible for emphasis, but the neutral order is Idi ravno.

Is okreni the same as skreni?

No:
- skreni = “turn (left/right)” at a junction.
- okreni (se) = “turn around / make a U‑turn” or “turn something”.
For “start moving,” use kreni (“set off”) or pođi (more formal/old‑fashioned).

How do I pronounce tricky sounds like lj in lijevo and š in škole?

lj is one palatal sound (similar to Italian “gl” in “famiglia”). Don’t pronounce separate “l” + “j”.
j sounds like English “y” in “yes”: li‑je‑vo.
š is like English “sh”: ško‑le.
Vowels are short and clear.

Is the imperative of ići really idi, not iđi?

Correct: idi. The verb stem is id‑ in most forms: idem, ideš, idu; idi. iđi is nonstandard.

Can I reorder parts like Kod škole skreni lijevo, pa idi ravno?

Yes. Croatian word order is flexible. Fronting Kod škole is natural and adds “At/by the school…” focus.
Keep the chronological sequence clear; the original order is the neutral, step‑by‑step instruction.

How would I make the instruction more polite or more concise?