Learn Hardcore Greek: Αύριο η γραμματεία ανοίγει στις δέκα το πρωί. - Tomorrow the office opens at ten in the morning.

It sounds normal and even a bit more natural than Αύριο η γραμματεία θα ανοίξει στις δέκα, which feels more like a single, one‑off future event rather than a fixed schedule.

So:

Αύριο η γραμματεία ανοίγει στις δέκα.
→ As part of the regular schedule, tomorrow it opens at ten.
Αύριο η γραμματεία θα ανοίξει στις δέκα.
→ It will open at ten tomorrow (maybe special / one‑time, or just more “neutral future”).

What exactly does η γραμματεία mean, and why is there an article?

Η γραμματεία is a feminine noun that usually means something like:

the secretary’s office
the secretariat
the administrative office / registrar’s office

In many contexts (universities, schools, organizations, clinics) η γραμματεία is the place/department where administrative tasks and paperwork are handled.

Greek uses the definite article much more often than English. Where English says:

Tomorrow the office opens at ten. or even Tomorrow the office opens at ten.

Greek virtually always uses the article:

Αύριο η γραμματεία ανοίγει στις δέκα.

Saying just Αύριο γραμματεία ανοίγει… without the article would sound wrong here.

Why is the article η (feminine) used with γραμματεία?

All Greek nouns have grammatical gender. Γραμματεία is a feminine noun, so it takes the feminine article:

η γραμματεία (nominative, “the office” – subject)
της γραμματείας (genitive, “of the office”)
τη(ν) γραμματεία (accusative, object)

So in this sentence, as the subject, you get:

η γραμματεία ανοίγει… → the office opens…

Why is there no article before Αύριο? Why don’t we say Το αύριο η γραμματεία…?

Αύριο here is not a noun; it’s an adverb of time, meaning tomorrow. In Greek, adverbs don’t take articles. Compare:

σήμερα – today
αύριο – tomorrow
χθες / χτες – yesterday

Just like in English we don’t say “the tomorrow the office opens…”, in Greek we also don’t put an article before αύριο.

You could put αύριο in different places in the sentence:

Αύριο η γραμματεία ανοίγει στις δέκα…
Η γραμματεία αύριο ανοίγει στις δέκα…
Η γραμματεία ανοίγει αύριο στις δέκα…

All are possible; they slightly shift the emphasis (often the first or last position is more emphatic).

What does στις mean in στις δέκα, and why is it στις and not στη?

Στις is the combination:

σε (preposition “at / in / to”)
τις (feminine plural definite article “the”)

So σε + τις = στις.

When telling the time with numbers from 2 to 12, Greek uses this fixed pattern:

στη μία – at one o’clock (singular: σε + τη)
στις δύο – at two
στις τρεις – at three
στις τέσσερις – at four
…
στις δέκα – at ten
στις έντεκα – at eleven
στις δώδεκα – at twelve

Historically, this agrees with an implied feminine plural noun (like ώρες, “hours”), but in practice you can treat στις + [number] as the standard way to say “at [time]” for all hours except one o’clock, which is στη μία.

So:

στις δέκα = at ten (o’clock)

Why is it στις δέκα and not στις δέκα η ώρα?

You can say στις δέκα η ώρα, but in everyday speech the noun η ώρα is usually omitted because it is understood from context.

Full form: Αύριο η γραμματεία ανοίγει στις δέκα η ώρα το πρωί.
Usual form: Αύριο η γραμματεία ανοίγει στις δέκα το πρωί.

Both are correct; the shorter one is more natural.

What is the function of το in το πρωί? Why is πρωί with an article?

Το πρωί literally means “the morning”, but as a time expression it functions like “in the morning”.

Greek often uses a definite article with parts of the day:

το πρωί – (in) the morning
το μεσημέρι – (at) noon / midday
το απόγευμα – (in) the afternoon
το βράδυ – (in) the evening / at night

So στις δέκα το πρωί = at ten in the morning.

Without the article (στις δέκα πρωί) it would sound wrong here.

Could the word order be different, for example Η γραμματεία αύριο ανοίγει στις δέκα το πρωί? Does it change the meaning?

Yes, you can change the word order; Greek is fairly flexible with this.

Possible orders include:

Αύριο η γραμματεία ανοίγει στις δέκα το πρωί.
(neutral, tomorrow is set as the time frame)
Η γραμματεία αύριο ανοίγει στις δέκα το πρωί.
(slight emphasis on γραμματεία as topic, then αύριο)
Η γραμματεία ανοίγει αύριο στις δέκα το πρωί.
(emphasis a bit more on ανοίγει αύριο as the important new info)

The basic meaning doesn’t change; it’s always “Tomorrow the office opens at ten in the morning.” The differences are mostly about rhythm and emphasis, not about the objective facts.

Could we say Η γραμματεία θα είναι ανοιχτή στις δέκα το πρωί instead of ανοίγει? What’s the difference?

Yes, that’s another correct way to express a future situation:

Η γραμματεία θα είναι ανοιχτή στις δέκα το πρωί.
→ The office will be open at ten in the morning.

Difference:

ανοίγει focuses on the event of opening (the action).
θα είναι ανοιχτή focuses on the state of being open at that time.

So if you care about when the doors will be unlocked / they start working, you say:

Αύριο η γραμματεία ανοίγει στις δέκα.

If you only need to know whether it will be open at that time (not necessarily the exact opening moment), you might say:

Η γραμματεία θα είναι ανοιχτή στις δέκα.

How is Αύριο η γραμματεία ανοίγει στις δέκα το πρωί pronounced, especially αύριο?

Approximate pronunciation (with stress marked by capitals):

Αύριο → Áv-rio (AV-rio)
- αυ before a consonant here is pronounced like av in “have”.
- The ρ is a tapped or slightly rolled r.
η γραμματεία → i gra-ma-TI-a
ανοίγει → a-NI-yi (the γγ / γ before front vowels often sounds like a soft y sound)
στις δέκα → stis THE-ka (δέκα: stress on δέ, and δ is a soft “th” as in “this”)
το πρωί → to pro-Í (stress on the last syllable -ί)

All together (very roughly in English spelling):
“AV-rio i gra-ma-TI-a a-NI-yi stis THE-ka to pro-Í.”