Learn Hardcore Polish: Po co idziesz do sklepu tak wcześnie? - What are you going to the store for so early?

Po co asks about purpose: “what for?” The natural answers are goals, often with an infinitive or with żeby
- infinitive. Example: Po co idziesz do sklepu? — Żeby kupić chleb. (To buy bread.)
Dlaczego asks about cause/reason: “why?” The natural answers are reasons, often with bo (“because”). Example: Dlaczego idziesz do sklepu? — Bo skończył się chleb. (Because we ran out of bread.)
In your sentence, Po co idziesz…? focuses on the intended purpose of the trip, not just the reason behind it.

Why is it do sklepu and not just do sklep?

The preposition do (“to, into”) requires the genitive case.
Sklep (store) in the genitive singular is sklepu. So: do sklepu = “to the store.”

Could I use na or w instead of do here?

For going to a store, the default is iść do sklepu.
Na is used with some destinations (often institutions/events/flat places): na pocztę (to the post office), na uniwersytet, na lotnisko, na dworzec. But for a typical shop, do sklepu is the norm.
W
- locative means “in/inside”: w sklepie = “in the store,” not “to the store.”

Why is it idziesz and not idzie or chodzisz?

Idziesz is 2nd person singular present (“you are going (on foot)”).
Idzie is 3rd person singular (“he/she/it is going”).
Chodzisz means “you go (habitually, on foot).” Use iść for a single, current/near-future trip; use chodzić for repeated action.
- One time/now: Idę do sklepu.
- Habitual: Chodzę do sklepu codziennie.

What if I’m going by car or bus? Do I still use iść?

Use a motion verb that matches the mode:
- On foot: iść (present) / pójść (future perfective).
- By vehicle: jechać (present) / pojechać (future perfective).
Your sentence assumes going on foot. If by car, say: Po co jedziesz do sklepu tak wcześnie?

Can idziesz refer to the near future, not just “right now”?

Yes. Polish often uses the present to talk about a planned near-future action:

Po co idziesz jutro do sklepu tak wcześnie? (What are you going to the store so early for tomorrow?) For a one-time future, you can also use the perfective: Po co pójdziesz…?

Where can I put tak wcześnie? Does word order matter?

Polish word order is flexible and used for emphasis:

Neutral/natural: Po co idziesz do sklepu tak wcześnie?
Emphasizing earliness: Po co tak wcześnie idziesz do sklepu?
Focus on destination: Po co do sklepu idziesz tak wcześnie? (more marked) All are grammatical; the end position is common and sounds natural.

Does po co ever sound judgmental?

It can. Po co…? may sound like “what’s the point of…?”, slightly challenging the usefulness of the action. If you want a neutral question about cause, use Dlaczego…? If you want a gentle question about plans/purpose, soften with tone or context: A po co idziesz…? or Po co właściwie idziesz…? (depending on tone).

How would I ask this politely to a stranger?

Use the polite 3rd-person forms with Pan/Pani:

To a man: Po co Pan idzie do sklepu tak wcześnie?
To a woman: Po co Pani idzie do sklepu tak wcześnie?

What’s the difference between wcześnie and wcześniej?

Wcześnie = “early” (in an absolute sense). Example: Wstaję wcześnie.
Wcześniej = “earlier” (comparative/relative). Example: Wstałem wcześniej niż zwykle. Your sentence needs the absolute adverb: tak wcześnie = “so early.”

Any pronunciation tips for wcześnie and idziesz?

wcześnie: the cluster wcz is devoiced and sounds like “f-ch” + “cz” together. Approx: “F-CHESH-nyeh.” IPA: [ˈft͡ʂɛɕɲɛ].
idziesz: dzi is a single soft sound [dʑ]. Approx: “EE-jyesh.” IPA: [ˈid͡ʑɛʂ].
Stress in Polish is usually on the second-to-last syllable: po CO iDZIesz do SKLEpu tak WCZEśnie.

Can I say what I’m going for, using po?

Yes. Po + accusative can express “to get/fetch”:

Idę po chleb. (I’m going to get bread.) You can combine both:
Purpose: Po co idziesz do sklepu? — Żeby kupić chleb.
Object of fetching: Po co idziesz? — Po chleb.