Learn Hardcore Greek: Ο υπάλληλος στο κατάστημα είναι ευγενικός.

Ο is the definite article in Greek, meaning “the” for a masculine singular noun in the nominative case (the case used for the subject of the sentence).

Ο υπάλληλος = the employee (as the subject)
It’s capitalized simply because it’s the first word of the sentence.

Greek almost always uses a definite article with singular countable nouns, even where English might leave it out, so saying Ο υπάλληλος is very normal and often more natural than just Υπάλληλος on its own.

What gender is υπάλληλος, and can it refer to a female employee too?

Grammatically, υπάλληλος is a noun that behaves like a masculine noun (ending in -ος), but it can refer to either a man or a woman, depending on the article and context.

ο υπάλληλος = the (male) employee
η υπάλληλος = the (female) employee

The noun form υπάλληλος stays the same; the article (ο vs η) shows whether you’re talking about a man or a woman.

So:

Ο υπάλληλος στο κατάστημα είναι ευγενικός.
= The (male) employee in the store is polite.
Η υπάλληλος στο κατάστημα είναι ευγενική.
= The (female) employee in the store is polite.
(Notice the adjective also changes to ευγενική, feminine.)

What exactly does στο mean, and why is it one word?

στο is a contraction of two words:

σε = in / at / to (a very common preposition)
το = the (neuter singular accusative article)

So:

σε + το = στο

In this sentence:

στο κατάστημα literally = in the store / at the store.

Greek very often contracts σε + article:

σε + το → στο
σε + τον → στον
σε + την → στη(ν)
σε + τους → στους
σε + τις → στις

So στο is written as one word because it’s this standard contraction.

Why is it στο κατάστημα and not στον κατάστημα?

Because κατάστημα is a neuter noun.

Neuter singular article (accusative): το
Masculine singular article (accusative): τον

The form στο = σε + το (for neuter nouns).
Στον = σε + τον (for masculine nouns).

So:

στο κατάστημα (neuter) = in/at the store
στον γιατρό (masculine) = at the doctor’s

Using στον κατάστημα would be incorrect because κατάστημα is not masculine; it’s neuter.

Why does it say κατάστημα here? Is it different from μαγαζί?

Both κατάστημα and μαγαζί can translate as “store / shop”, but there is a nuance:

κατάστημα: more formal, can sound a bit more “official” or business-like (e.g. εμπορικό κατάστημα = commercial store).
μαγαζί: more colloquial, everyday word for shop, bar, small business, etc.

In everyday speech you’d often hear:

Ο υπάλληλος στο μαγαζί είναι ευγενικός.

The sentence with κατάστημα is perfectly correct; it just leans slightly more neutral/formal.

What form of the verb is είναι, and why don’t we see “he” or “she” written?

είναι is the 3rd person singular form of the verb είμαι (to be) in the present tense.

The main present forms of είμαι are:

(εγώ) είμαι = I am
(εσύ) είσαι = you are (singular)
(αυτός/αυτή/αυτό) είναι = he / she / it is
(εμείς) είμαστε = we are
(εσείς) είστε = you are (plural / polite)
(αυτοί/αυτές/αυτά) είναι = they are

Greek is a pro‑drop language: the subject pronoun (he, she, it) is often omitted because the verb ending already tells you the person.

So instead of:

Αυτός είναι ευγενικός. (He is polite.)

You usually just say:

Είναι ευγενικός. (He is polite.) — the αυτός is understood from context.

In our sentence, Ο υπάλληλος is clearly the subject, so no extra “he” is needed.

Why is the adjective ευγενικός placed at the end? Can it go before υπάλληλος?

In this sentence, ευγενικός is a predicate adjective linked to the subject by the verb είναι:

Ο υπάλληλος … είναι ευγενικός.
= The employee … is polite.

Typical Greek structure here is:

[Subject] + [είναι] + [adjective]
→ Ο υπάλληλος είναι ευγενικός.

You can move things around a bit for emphasis:

Ο υπάλληλος είναι πολύ ευγενικός. (same meaning)
Ευγενικός είναι ο υπάλληλος στο κατάστημα. (emphasis on “polite”)

However, if you put the adjective directly before the noun, it usually becomes attributive, describing which employee:

Ο ευγενικός υπάλληλος στο κατάστημα
= the polite employee in the store (as a noun phrase, not a full sentence)

So:

Ο υπάλληλος στο κατάστημα είναι ευγενικός.
= The employee is polite.
Ο ευγενικός υπάλληλος στο κατάστημα…
= The polite employee in the store… (you still need a verb to make a full sentence)

Why does ευγενικός end in -ός? How would it change with feminine or plural nouns?

ευγενικός is a regular adjective of the -ός, -ή, -ό type. It agrees with the noun’s gender, number, and case.

Basic nominative forms:

Masculine: ευγενικός
Feminine: ευγενική
Neuter: ευγενικό

So:

Ο υπάλληλος είναι ευγενικός.
(masc. sg.) = The employee is polite. (male)
Η υπάλληλος είναι ευγενική.
(fem. sg.) = The employee is polite. (female)
Το παιδί είναι ευγενικό.
(neut. sg.) = The child is polite.

Plural nominative:

Masculine: ευγενικοί
Feminine: ευγενικές
Neuter: ευγενικά

Example with our noun:

Οι υπάλληλοι στο κατάστημα είναι ευγενικοί.
= The employees in the store are polite. (masculine / mixed group)

Does ευγενικός only mean “polite”, or does it have other shades of meaning?

The core meaning of ευγενικός is polite / courteous / well‑mannered.

Depending on context, it can suggest:

courteous in behavior (saying please/thank you, speaking nicely)
kind / considerate (treating people with respect)
sometimes gentlemanly / chivalrous, especially about a man’s behavior toward others

It does not usually mean “generous” (that would be γενναιόδωρος), and it’s not about social class “noble” in modern everyday use (though historically related).

In this sentence it’s best understood as:

“The employee in the store is polite / courteous / well‑mannered.”

How would I say “The employee in the store is not polite” in Greek?

You make it negative by putting δεν directly before the verb είναι:

Ο υπάλληλος στο κατάστημα δεν είναι ευγενικός.
= The employee in the store is not polite.

Pattern:

[Subject] + δεν + [verb] + [rest of sentence]

Note: δεν becomes δε in front of some consonants in fast or informal speech, but δεν είναι is standard and correct.

How do I make this sentence plural: “The employees in the store are polite”?

You need to put the article, noun, and adjective in the plural, and είναι stays the same (it’s also the 3rd person plural form):

Οι υπάλληλοι στο κατάστημα είναι ευγενικοί.

Changes:

Ο υπάλληλος → Οι υπάλληλοι (the employees)
είναι → είναι (same form for “is” and “are”)
ευγενικός → ευγενικοί (masculine plural to agree with υπάλληλοι)

Meaning:

Οι υπάλληλοι στο κατάστημα είναι ευγενικοί.
= The employees in the store are polite.

How do you pronounce Ο υπάλληλος στο κατάστημα είναι ευγενικός?

Approximate pronunciation:

O ipÁlilos sto katÁstima Íne evyenikÓs

Where the capital letters show the stressed syllables:

iPÁ‑li‑los
ka‑TÁ‑sti‑ma
Í‑ne
ev‑ye‑ni‑KÓS

In IPA (one possible transcription):

/o iˈpalilos sto kaˈtastima ˈine evʝeniˈkos/

Why do the words have accent marks (´) like υπάλληλος, κατάστημα, ευγενικός? What do they tell me?

In Modern Greek, almost every word with more than one syllable has one written accent mark (´) over a vowel. It shows you which syllable is stressed.

In this sentence:

υπάλληλος → stress on πά → υπά‑λλη‑λος
κατάστημα → stress on τά → κα‑τά‑στη‑μα
είναι → stress on εί → εί‑ναι
ευγενικός → stress on κός → ευ‑γε‑νι‑κός

Accent marks are crucial for correct pronunciation and sometimes for distinguishing between different words. They must appear in writing, not just in dictionaries.