Learn Hardcore Greek: Δεν θέλω να είμαι εθισμένος στο τηλέφωνο, γι’ αυτό πρέπει να πολεμήσω αυτή τη συνήθεια. - I don’t want to be addicted to the phone, so I must fight this habit.

δεν (before consonants) / δε (before some voiced consonants): used with indicative verbs (normal statements of fact).
μη(ν): used mainly with subjunctive, imperative, and some fixed expressions.

In the sentence, θέλω is a normal present-indicative verb (I want), so the correct negation is δεν θέλω = I don’t want.

You will see μην later in the same sentence: πρέπει να πολεμήσω could become δεν πρέπει να πολεμήσω / μην πολεμήσεις!, etc. But for θέλω, in this simple indicative form, you use δεν.

Why is it θέλω να είμαι εθισμένος instead of something like an infinitive “to be addicted”?

Modern Greek does not have an infinitive like English to be, to go, to eat.

Instead, it uses να + finite verb (subjunctive form). So:

English: I don’t want *to be addicted.*
Greek: Δεν θέλω να είμαι εθισμένος.
Literally: I don’t want that I be addicted.

Key point: after verbs like θέλω (want), πρέπει (must), μπορώ (can), you normally use να + verb, not an infinitive, because the infinitive no longer exists in Modern Greek.

What exactly is εθισμένος? Is it an adjective or a verb form?

Εθισμένος is a participle used as an adjective, meaning addicted.

It comes from the verb εθίζω / εθίζομαι (to addict / to get addicted).
It agrees in gender, number, and case with the subject:
- εθισμένος (masc. sg.)
- εθισμένη (fem. sg.)
- εθισμένο (neut. sg.)

In the sentence, the subject is (εγώ) I, a male speaker (or grammatically masculine form), so:

Δεν θέλω να είμαι εθισμένος…
I don’t want to be addicted…

If a woman was speaking, she would say:

Δεν θέλω να είμαι εθισμένη στο τηλέφωνο.

Why is there no article before εθισμένος? Why not ο εθισμένος?

Here εθισμένος is used in a predicate position after the verb είμαι (to be), just like:

είμαι κουρασμένος = I am tired
είμαι χαρούμενος = I am happy

In this position, Greek normally does not use an article:

είμαι εθισμένος = I am addicted

If you add an article (ο εθισμένος), it becomes a noun phrase, something like the addicted (guy/person), not a description of your state. That would change the meaning.

Why do we say στο τηλέφωνο and not, for example, με το τηλέφωνο?

Στο is the contraction of σε + το, and it often corresponds to English on, at, in, to, depending on context.

στο τηλέφωνο literally: on/at the phone
Idiomatically: on the phone / on my phone (here meaning “addicted to the phone / to phone use”).

Using με το τηλέφωνο (with the phone) would usually sound like you are doing something together with the phone (as an instrument/tool), not that you’re addicted to it. So:

εθισμένος στο τηλέφωνο = addicted to the phone (correct)
εθισμένος με το τηλέφωνο = unnatural in Greek for this meaning.

What does γι’ αυτό mean exactly, and why is there an apostrophe?

Γι’ αυτό is a contraction of για αυτό:

για = for
αυτό = this (neuter demonstrative pronoun)

Together, γι’ αυτό literally means for this (reason) and is used like “therefore / that’s why / so”.

The apostrophe marks elision: the final vowel -α of για is dropped before αυτό, because Greek avoids two identical vowels meeting:

για αυτό → γι’ αυτό

So in the sentence:

…στο τηλέφωνο, γι’ αυτό πρέπει να πολεμήσω…
= …on the phone, that’s why I must fight…

Why is it πρέπει να πολεμήσω and not πρέπει να πολεμάω / πολεμώ?

Greek verbs have two main aspects:

Imperfective (ongoing/repeated): πολεμάω / πολεμώ = I fight / I keep fighting
Aorist (single, complete action): πολεμήσω (subj.) = that I fight (as a whole, a completed effort)

After πρέπει να (I must / I have to), you can use either aspect, but the nuance changes:

πρέπει να πολεμήσω αυτή τη συνήθεια
→ I must (decisively) fight it / break it (focus on achieving a result).
πρέπει να πολεμάω αυτή τη συνήθεια
→ I must keep fighting this habit (emphasis on ongoing struggle).

In the given sentence, the aorist πολεμήσω suggests a determined effort to overcome the habit.

How does αυτή τη συνήθεια work? Why isn’t it αυτή η συνήθεια?

Greek demonstratives plus nouns use different patterns for subject vs object.

Subject (nominative) pattern:
- αυτή η συνήθεια = this habit (as the subject)
- e.g. Αυτή η συνήθεια είναι κακή. = This habit is bad.
Object (accusative) pattern:
- αυτή τη συνήθεια = this habit (as the object)
- e.g. Πρέπει να πολεμήσω αυτή τη συνήθεια.
  → I must fight this habit.

In our sentence, τη συνήθεια is the object of πολεμήσω, so it must be in the accusative:

αυτή τη συνήθεια (not αυτή η συνήθεια).

Why is it αυτή τη συνήθεια and not αυτήν τη συνήθεια?

Formally, the feminine accusative singular demonstrative is αυτήν, but in everyday spoken and written Modern Greek, the final -ν is often dropped before consonants:

αυτήν τη συνήθεια → αυτή τη συνήθεια

Keeping the -ν is more common:

before vowels, or
before certain consonants (π, τ, κ, μπ, ντ, γκ, ξ, ψ)

So both are grammatically correct; αυτή τη συνήθεια is simply the more natural, common form in this context.

Why is τηλέφωνο neuter and συνήθεια feminine? How do I know the gender?

In Greek, grammatical gender is a property of nouns and must be learned:

το τηλέφωνο = the phone (neuter)
η συνήθεια = the habit (feminine)

There are some useful patterns:

Many neuter nouns end in -ο, -ι, -μα:
το τηλέφωνο, το σπίτι, το γράμμα
Many feminine nouns end in -α, -η:
η συνήθεια, η μέρα, η πόλη

The articles show you the gender:

το τηλέφωνο → neuter
η συνήθεια → feminine
In the accusative: τη συνήθεια (that’s what you see in the sentence).

Why is there a comma before γι’ αυτό in the sentence?

The comma separates two clauses:

Δεν θέλω να είμαι εθισμένος στο τηλέφωνο
= I don’t want to be addicted to the phone
γι’ αυτό πρέπει να πολεμήσω αυτή τη συνήθεια
= so / that’s why I must fight this habit

Γι’ αυτό introduces the result / consequence clause, similar to English so, therefore, that’s why. Greek punctuation rules, like English, use a comma to separate these two independent (or semi‑independent) clauses.