Learn Hardcore Greek: Όταν διαλέξω ρούχα, πηγαίνω στο ταμείο όπου ο ταμίας χαμογελάει ευγενικά. - When I choose clothes, I go to the checkout where the cashier smiles politely.

Όταν διαλέγω ρούχα… = When I choose clothes (whenever I’m shopping / habitually)…
→ Focus on a repeated / ongoing action.
Όταν διαλέξω ρούχα… = When I (have) chosen the clothes (on that occasion)…
→ Focus on a single, complete event that finishes before the next action (“I go to the checkout”).

So διαλέξω presents the choosing as a single completed step before going to the checkout, rather than a general habit. Many speakers would also use διαλέγω here if they wanted a more clearly habitual meaning.

Is διαλέξω in the subjunctive? How can I tell?

Yes, διαλέξω here is aorist subjunctive.

You can tell because:

It has the typical aorist stem (διαλέξ‑) plus subjunctive ending -ω (as in να διαλέξω = that I choose).
After conjunctions like όταν (when), αν (if), πριν (before), Greek often uses the subjunctive to talk about future or uncertain events:
- Όταν διαλέξω ρούχα, … = When I choose clothes (in the future / at some time), …

There is no να written here, but many conjunctions in Greek take subjunctive without needing να.

Does όταν always take the subjunctive?

No, όταν does not always take the subjunctive.

For general / habitual situations, you normally see the present indicative:
- Όταν διαλέγω ρούχα, πηγαίνω στο ταμείο.
  When I choose clothes (in general), I go to the checkout.
For single future events or events seen as a single completed step, you often see the subjunctive (aorist or present):
- Όταν διαλέξω ρούχα, θα πάω στο ταμείο.
  When I choose the clothes, I’ll go to the checkout.

In your sentence, διαλέξω makes the choosing sound like one complete event before you go to the checkout.

Why is there a comma after ρούχα?

The comma separates the dependent clause from the main clause:

Dependent clause: Όταν διαλέξω ρούχα,
Main clause: πηγαίνω στο ταμείο όπου ο ταμίας χαμογελάει ευγενικά.

In Greek, when a clause introduced by όταν, αν, επειδή, etc. comes first, it is normally followed by a comma, much like in English:

When I choose clothes, I go to the checkout…

Why do we say στο ταμείο and not σε το ταμείο?

Στο is simply the contracted form of σε + το.

σε + το ταμείο → στο ταμείο
Similarly: σε + τον ταμία → στον ταμία, σε + την πόλη → στην πόλη

In modern Greek, you must use the contracted form in normal speech; σε το ταμείο is not used.

Why does ταμίας have the article ο in front of it?

Greek uses the definite article much more often than English, especially with professions and roles.

ο ταμίας = the cashier (male)
η ταμίας or η ταμίας / η ταμίας-υπάλληλος is also used for a female cashier, depending on register.

Even when English might say just “where a cashier smiles politely”, Greek tends to say όπου ο ταμίας χαμογελάει ευγενικά with the article. It can refer to the cashier at that particular checkout that both speaker and listener know about.

What is the difference between όπου and που here?

Both όπου and που can introduce a relative clause, but:

όπου literally has the idea of “where / at which place”, and is natural when you are talking about a location:
- στο ταμείο όπου ο ταμίας χαμογελάει
  at the checkout where the cashier smiles
που is a very general relative pronoun (“that, which, who”) and is extremely common:
- στο ταμείο που ο ταμίας χαμογελάει

In this sentence, όπου emphasizes that the second action happens at that place (the checkout). Using που would be grammatically fine but slightly less explicitly “locative” / place-focused.

Why is ο ταμίας in the nominative case after όπου?

Because ο ταμίας is the subject of the verb χαμογελάει.

The structure is:

στο ταμείο → prepositional phrase (“to/at the checkout”)
όπου → relative word linking to a new clause
ο ταμίας χαμογελάει ευγενικά → full clause: the cashier smiles politely

Inside that clause, ο ταμίας does the action “smiles”, so it is in the nominative just like any other subject. The word όπου doesn’t change the case of the noun that follows; it just links the clauses.

Is there any difference between χαμογελάει and χαμογελά?

Both χαμογελάει and χαμογελά are correct and mean “he/she smiles”.

Verb: χαμογελάω / χαμογελώ = to smile
3rd person singular forms:
- χαμογελάει (more colloquial in many areas)
- χαμογελά (a bit shorter, sometimes felt as slightly more “standard” or more formal, but both are widely used)

In everyday speech, χαμογελάει is extremely common. You can usually choose either without changing the meaning.

How is the adverb ευγενικά formed, and where does it go in the sentence?

Ευγενικά is the adverb meaning “politely”, formed from the adjective ευγενικός (polite).

Masculine: ευγενικός
Feminine: ευγενική
Neuter: ευγενικό
Adverb: ευγενικά

In this sentence, it comes after the verb:

ο ταμίας χαμογελάει ευγενικά = the cashier smiles politely

Adverbs of manner (how?) in Greek usually go after the verb, but you can sometimes move them for emphasis:

ο ταμίας ευγενικά χαμογελάει (more emphasis on “politely”)

Why is the subject “I” not written in Greek?

Greek is a “pro‑drop” language: you usually omit subject pronouns (εγώ, εσύ, αυτός…) because the verb ending already tells you who the subject is.

διαλέξω → 1st person singular (“I choose”)
πηγαίνω → 1st person singular (“I go”)

So Όταν διαλέξω ρούχα, πηγαίνω στο ταμείο… automatically means When I choose clothes, I go to the checkout… without needing to say εγώ. You only add εγώ for emphasis or contrast (e.g. εγώ πηγαίνω στο ταμείο = I go to the checkout (not someone else)).

Could I say πάω instead of πηγαίνω? Is there a difference?

Yes, you can say πάω instead of πηγαίνω here:

Όταν διαλέξω ρούχα, πάω στο ταμείο…

In modern Greek:

πάω is very common and a bit more colloquial/short.
πηγαίνω is slightly more neutral or formal, and can also emphasize repeated / regular movement in some contexts.

In most everyday situations they are interchangeable, and both sound natural in this sentence.

Why is ρούχα used without an article? Could we say τα ρούχα instead?

Here ρούχα appears without an article because it’s being used in a general / indefinite sense: clothes (in general).

Όταν διαλέξω ρούχα… = When I choose clothes… (not specific ones already known)

You could say Όταν διαλέξω τα ρούχα…, but that sounds like you mean some specific clothes already identified (“the clothes we talked about / the clothes on the bed”, etc.).

So:

ρούχα (no article) → generic, “some clothes / clothes in general”
τα ρούχα → specific, “the clothes” (those particular clothes)