Learn Hardcore Greek: Κάθε Τρίτη πίνω καφέ με τη συνάδελφό μου. - Every Tuesday I drink coffee with my colleague female.

The noun ο καφές (coffee) is masculine:
- Nominative (subject): ο καφές – Ο καφές είναι ζεστός. (The coffee is hot.)
- Accusative (object): (τον) καφέ – Πίνω καφέ. / Πίνω τον καφέ. (I drink coffee / I drink the coffee.)

In πίνω καφέ, coffee is the thing you drink (object), so it must be καφέ, not καφές.

Why is there no article before καφέ? Why not πίνω έναν καφέ?

Both are possible, but they mean slightly different things.

πίνω καφέ
Literally: I drink coffee.
Used:
- for the activity in general (I drink coffee / I have coffee as a habit)
- for an unspecified amount (some coffee)
πίνω έναν καφέ
Literally: I drink a coffee (one coffee).
Used when you think of one serving / one cup.

In Κάθε Τρίτη πίνω καφέ, the focus is the regular activity, so Greek naturally drops the article. You could also say Κάθε Τρίτη πίνω έναν καφέ, with a slight nuance of “a (single) coffee every Tuesday”.

What exactly does κάθε Τρίτη mean? How is it different from την Τρίτη?

κάθε Τρίτη = every Tuesday, a repeated, habitual action.
- Κάθε Τρίτη πίνω καφέ. – Every Tuesday I drink coffee.
την Τρίτη (without κάθε) = on Tuesday, usually one specific Tuesday (past or future, depending on context).
- Την Τρίτη πίνω καφέ με τη συνάδελφό μου. – On Tuesday I’m having coffee with my colleague (this particular Tuesday).

So κάθε Τρίτη always implies regular repetition, not just a one‑off event.

Why is there no word for “on” before Κάθε Τρίτη?

In Greek, dates and days in time expressions normally stand on their own in the accusative, without a preposition:

Κάθε Δευτέρα δουλεύω. – Every Monday I work.
Την Παρασκευή φεύγω. – On Friday I leave.
Κάθε βράδυ διαβάζω. – Every evening I read.

So Κάθε Τρίτη πίνω καφέ already means “On every Tuesday I drink coffee”; you don’t add a separate word for “on”.

Can I change the word order, or must it be Κάθε Τρίτη πίνω καφέ…?

You can change the order quite freely. All of these are grammatical:

Κάθε Τρίτη πίνω καφέ με τη συνάδελφό μου.
Πίνω καφέ με τη συνάδελφό μου κάθε Τρίτη.
Με τη συνάδελφό μου πίνω καφέ κάθε Τρίτη.

The basic meaning stays the same. Differences are about emphasis:

Starting with Κάθε Τρίτη slightly emphasizes the time (how regularly you do it).
Putting κάθε Τρίτη at the end can sound more like an afterthought or extra detail.

But in everyday speech, all these orders are very normal.

Why is it με τη συνάδελφό μου and not η συνάδελφός μου?

Two things are going on:

The preposition με (“with”) requires the accusative case.
- Subject (nominative): η συνάδελφός μου – Η συνάδελφός μου πίνει καφέ. (My colleague is drinking coffee.)
- With με (accusative): με τη συνάδελφό μου – Πίνω καφέ με τη συνάδελφό μου. (I drink coffee with my colleague.)
In Greek, the possessive pronoun μου normally comes after the noun, not before it:
- η συνάδελφός μου = my colleague
- το βιβλίο μου = my book

So the form after με must be accusative: με τη συνάδελφό μου, not η συνάδελφός μου.

Why is it τη and not την before συνάδελφό?

Both forms exist: τη and την are the same article (feminine accusative singular). The -ν at the end is often dropped.

Standard modern rule (for την, τον, έναν):

Keep -ν before:
- vowels: την αδελφή μου
- and the consonants: κ, π, τ, ξ, ψ, μπ, ντ, γκ, τσ, τζ
  - την καρέκλα, την πόρτα, την τσάντα…
Elsewhere, dropping -ν is normal:
- τη συνάδελφό μου (σ, not in that list)
- τη μητέρα μου

You can still hear and see την συνάδελφό μου, but in contemporary usage τη συνάδελφό μου is more standard.

Why does συνάδελφό have an accent on the last syllable as well? (τη συνάδελφό μου)

The basic noun is:

Nominative: η συνάδελφος
Accusative: τη συνάδελφο (accent only on ά)

When you add the enclitic pronoun μου, Greek spelling rules add a second accent on the last syllable of the noun:

τη συνάδελφό μου

This happens because συνάδελφος is stressed three syllables from the end (συ‑νά‑δελ‑φος).
With an enclitic like μου, the whole group counts as one unit, and the writing rule is:
words stressed that far from the end get a second written accent when followed by an enclitic.

You’ll see the same pattern in other words:

ο άνθρωπος → ο άνθρωπός μου
η άσκηση → η άσκησή μου

For speaking, you don’t need to worry too much: just memorize τη συνάδελφό μου as the correct written form.

Is συνάδελφος masculine or feminine? How do I know?

συνάδελφος is a common‑gender noun: the same form is used for both men and women. The article and other words around it tell you the gender.

ο συνάδελφος = the male colleague
η συνάδελφος = the female colleague

In your sentence:

τη συνάδελφό μου → τη is feminine, so here it refers to a female colleague.

If you meant a male colleague, you would say:

με τον συνάδελφό μου – with my (male) colleague.

Does πίνω mean “I drink” or “I am drinking”?

πίνω covers both English meanings:

Habit / general truth:
- Κάθε Τρίτη πίνω καφέ. – Every Tuesday I drink coffee.
Action happening now:
- Τώρα πίνω καφέ. – I am drinking coffee now.

Greek has one present tense (πίνω) that corresponds to both English simple present and present continuous. Context and time expressions (κάθε Τρίτη, τώρα, συνήθως, etc.) show which reading is meant.

Why is Τρίτη capitalized? Are days of the week capitalized in Greek?

In standard modern Greek spelling, days of the week are usually written with a lowercase initial:

κάθε Δευτέρα, κάθε Τρίτη, κάθε Τετάρτη …

So many writers would prefer:

κάθε Τρίτη πίνω καφέ…

However:

At the start of a sentence, the first word is capitalized (Κάθε here).
In some books, teaching materials, or under the influence of English, you will see days capitalized (like Τρίτη) even in the middle of a sentence.

For your own writing, using lowercase for days (κάθε Τρίτη) is the safer, more standard choice.