Learn Hardcore Greek: Είναι πιθανό να χρειαστώ περισσότερη φροντίδα όταν θα ζω μόνος μου στο εξωτερικό. - It is possible that I will need more care when I live alone abroad.

We use the aorist subjunctive (χρειαστώ) instead of the present (χρειάζομαι) because we are talking about needing (at some point / in general as a possibility), not about an ongoing process of needing. The aorist subjunctive often expresses the idea of “at some point / in a particular situation”, which fits “might need more care” well.

Why is it να χρειαστώ and not θα χρειαστώ? They both seem like “I will need”.

Να χρειαστώ and θα χρειαστώ are not the same:

Να χρειαστώ = subjunctive after είναι πιθανό.
Structure: Είναι πιθανό + να + subjunctive = It is possible that…
Θα χρειαστώ = simple future (indicative) = I will need (more definite).

If you said:

Είναι πιθανό θα χρειαστώ περισσότερη φροντίδα…

this would be wrong in standard Greek, because είναι πιθανό requires να + subjunctive, not θα + future.

So the pattern is:

Είναι πιθανό να χρειαστώ… ✔️
Θα χρειαστώ… ✔️ (without είναι πιθανό)
Είναι πιθανό θα χρειαστώ… ✖️

What is the function of Είναι πιθανό here, and how is it different from Μπορεί να or Ίσως?

Είναι πιθανό is an impersonal phrase meaning “it is likely / it is possible” and it takes να + subjunctive:

Είναι πιθανό να χρειαστώ περισσότερη φροντίδα…

Similar expressions:

Μπορεί να χρειαστώ περισσότερη φροντίδα…
= I may/might need more care.
Very natural and common in speech, a bit more casual.
Ίσως χρειαστώ περισσότερη φροντίδα…
or Ίσως να χρειαστώ περισσότερη φροντίδα…
= Maybe I will need more care.

Roughly:

Είναι πιθανό να… – slightly more formal, explicit “it is likely that…”
Μπορεί να… – very common, neutral; “may / might”
Ίσως (να)… – “maybe / perhaps”

All three are acceptable here with small differences in style.

Why is it όταν θα ζω and not just όταν ζω? In English we say “when I live”, not “when I will live”.

This is an area where Greek and English differ.

In Greek, with future time after όταν (when), you often hear:

όταν θα ζω μόνος μου στο εξωτερικό
literally: when I will be living on my own abroad

Both of these are used in modern Greek:

όταν ζω μόνος μου στο εξωτερικό
όταν θα ζω μόνος μου στο εξωτερικό

Depending on speaker and context, the θα can be:

omitted (more standard/neutral, especially in writing)
or included (very common in everyday speech)

So:

Όταν ζω μόνος μου στο εξωτερικό – fully correct, many teachers prefer this.
Όταν θα ζω μόνος μου στο εξωτερικό – also common, especially in spoken Greek, and understood as future.

Your sentence uses the spoken-style variant with θα.

Why do we have ζω and not ζήσω here? What is the difference?

Ζω and ζήσω differ in aspect:

ζω = present/imperfective: I live / I am living
ζήσω = aorist subjunctive (or simple future with θα): I live (at some point) / I will live (once)

In όταν θα ζω μόνος μου στο εξωτερικό, the focus is on the state / ongoing situation of living abroad for a period of time:

όταν θα ζω μόνος μου στο εξωτερικό
= when I am living on my own abroad (during that period of my life)

If you said όταν θα ζήσω, it would sound more like “the moment/once I have lived”, which is not natural here. For ongoing situations, ζω is the right choice.

What is the difference between ζω and μένω in this kind of sentence? Could I say όταν θα μένω μόνος μου?

Both can work, but they are not identical:

ζω = to live, in a more general sense (life, lifestyle, existence)
μένω = to stay / to reside / to live (somewhere), more about residence or staying in a place

In your sentence:

όταν θα ζω μόνος μου στο εξωτερικό
emphasizes the overall life situation: living alone abroad, your daily life, conditions.

If you say:

όταν θα μένω μόνος μου στο εξωτερικό

it’s also understandable and can be used, but it puts a bit more emphasis on residing / staying in a place abroad. In practice, Greek speakers do use μένω for “I live in X city”, so both are common; ζω sounds slightly broader and more “existential”.

Why is it περισσότερη φροντίδα and not περισσότερο φροντίδα?

Περισσότερος / -η / -ο is an adjective that agrees with the noun:

Masculine: περισσότερος
Feminine: περισσότερη
Neuter: περισσότερο

Φροντίδα is a feminine noun (η φροντίδα), so you must use the feminine form:

περισσότερη φροντίδα = more care

If the noun were neuter, you’d say:

περισσότερο νερό (neuter: το νερό) = more water

So:

περισσότερη φροντίδα ✔️
περισσότερο φροντίδα ✖️ (wrong agreement)

What exactly does φροντίδα mean here? Is it “care”, “attention”, or something like “support”?

Φροντίδα generally means care in the sense of:

looking after someone
providing help, support, supervision, assistance
sometimes also emotional or medical care

In this specific sentence:

περισσότερη φροντίδα
suggests you might need more support / more looking after, for example help with daily life, health, emotional support, etc., depending on context.

It is broader than just “attention”; it’s more like care and support.

Why do we say μόνος μου and not just μόνος? What is the role of μου here?

Μόνος is an adjective meaning alone (masculine: μόνος, feminine: μόνη, neuter: μόνο).

Ζω μόνος = I live alone.

However, in everyday Greek it’s very common (and more natural-sounding) to add a possessive pronoun for emphasis or naturalness:

ζω μόνος μου literally: I live alone by myself

The μου here is not “my” in the usual ownership sense; it is a clitic pronoun used idiomatically to strengthen the idea that I am by myself, with no one else.

Similar patterns:

το έκανα μόνος μου = I did it by myself
θα τα καταφέρω μόνος μου = I’ll manage on my own

So μόνος is correct, but μόνος μου feels more natural and idiomatic.

Why is it μόνος μου (masculine) and not μόνη μου or μόνο μου?

Μόνος / μόνη / μόνο must agree with the gender and number of the subject.

Here the (understood) subject is εγώ (I):

If the speaker is a man, then: εγώ → masculine → μόνος μου
If the speaker is a woman, then: εγώ → feminine → μόνη μου

So:

A male speaker:
Είναι πιθανό να χρειαστώ περισσότερη φροντίδα όταν θα ζω μόνος μου στο εξωτερικό.
A female speaker would normally say:
Είναι πιθανό να χρειαστώ περισσότερη φροντίδα όταν θα ζω μόνη μου στο εξωτερικό.

Μόνο μου (neuter) is used when the subject is neuter, for example:

το παιδί μόνο του = the child on its own.

What does στο εξωτερικό literally mean, and why is it not something like σε εξωτερικό?

Το εξωτερικό is a fixed noun in Greek meaning “abroad / foreign countries” as a general concept.

το εξωτερικό = abroad, foreign parts
στο εξωτερικό = σε + το εξωτερικό = abroad / overseas

We almost always say:

στο εξωτερικό = abroad
από το εξωτερικό = from abroad

You would not say:

σε εξωτερικό ✖️
στον εξωτερικό ✖️ (here εξωτερικό is not used as an adjective; it’s a noun)

So στο εξωτερικό is an idiomatic expression meaning “abroad”, not “in the outside” in a literal physical sense.

Why is there no εγώ in the sentence? How do we know it means “I might need more care”?

Greek is a pro-drop language: subject pronouns are usually omitted because the verb ending already shows the person.

In να χρειαστώ:

ending -ώ = first person singular → I

So:

Είναι πιθανό να χρειαστώ περισσότερη φροντίδα…
is clearly understood as
It is possible that I will need more care…

You could add εγώ for emphasis:

Είναι πιθανό εγώ να χρειαστώ περισσότερη φροντίδα…

but this usually sounds like you’re contrasting yourself with others (e.g. “I, not someone else, might need more care”). In normal, neutral statements, εγώ is left out.