Learn Hardcore Greek: Το πρωί το απαλό φως από την μπαλκονόπορτα με ξυπνάει, αλλά το μεσημέρι το φως γίνεται πιο σκληρό. - In the morning the soft light from the balcony door wakes me up, but at noon the light becomes harsher.

So το πρωί here doesn’t mean a specific “the morning” of one day; it means the general time of day, like a habitual “in the morning” in English.
The same with το μεσημέρι = “at noon (generally, at that time of day).”

Why is το repeated before απαλό φως? Why not just Το πρωί απαλό φως από την μπαλκονόπορτα με ξυπνάει?

The second το belongs to το φως (“the light”), which is the subject of the verb:

Το πρωί – time phrase (“in the morning”)
το απαλό φως από την μπαλκονόπορτα – subject (“the soft light from the balcony door”)
με ξυπνάει – verb + object (“wakes me up”)

If you drop the article and say Το πρωί απαλό φως…, it sounds more like “some soft light…” (more vague/indefinite), and it is also less natural word order for a clear, definite subject.
With το απαλό φως you are talking about that specific, known light that comes in every morning.

What does με in με ξυπνάει mean, and where does it go in the sentence?

με is the unstressed object pronoun “me” (accusative of εγώ = “I”).

με ξυπνάει = “(it) wakes me up”

Typical position: με goes right before the verb in simple sentences:

Το απαλό φως με ξυπνάει. – “The soft light wakes me up.”

In more complex sentences, it can attach to other verbs (e.g. after an infinitive-like form), but the default for beginners to learn is: unstressed object pronouns (με, σε, τον, την, το, μας, σας, τους) normally come immediately before the verb in main clauses.

Why is it απαλό φως and not απαλή φως?

Because φως is a neuter noun, so the adjective must also be in the neuter form.

το φως – neuter singular
Adjective “soft”: απαλός (masc.), απαλή (fem.), απαλό (neut.)

So you must say:

το απαλό φως – neuter article + neuter adjective + neuter noun

απαλή is the feminine form and would be used with a feminine noun, e.g. η απαλή μουσική (“the soft music”).

What is the difference between ξυπνάει, ξυπνά, and ξυπνάω?

They are different forms of the same verb ξυπνάω / ξυπνώ (“to wake (up)”).

1st person singular:
- ξυπνάω / ξυπνώ – “I wake (up)”
3rd person singular:
- ξυπνάει / ξυπνά – “he/she/it wakes (up)”

In spoken Modern Greek, ξυπνάει and ξυπνά are both common for the 3rd person singular; ξυπνάω or ξυπνώ is 1st person. In με ξυπνάει, the subject is “the light” (3rd person), so 3rd person singular is required.

What is the subject of με ξυπνάει? There’s no “it” written in Greek.

The subject is το απαλό φως από την μπαλκονόπορτα (“the soft light from the balcony door”).

Greek normally drops subject pronouns when the subject is obvious from context or already expressed. You don’t write an extra αυτό (“it”) the way English does:

Το απαλό φως από την μπαλκονόπορτα με ξυπνάει.
Literally: “The soft light from the balcony door wakes-me.”

So there is a clear subject; it is just a noun phrase, not a pronoun “it”.

Why do we use γίνεται here instead of just είναι?

γίνεται (from γίνομαι) means “becomes / turns / gets,” expressing a change of state:

το φως γίνεται πιο σκληρό – “the light becomes / gets harsher”

If you said:

Το μεσημέρι το φως είναι πιο σκληρό.

that would mean “At noon the light is harsher” (a simple statement of fact).
With γίνεται, the sentence highlights the transition: it’s soft in the morning, then by noon it becomes harder.

How does πιο σκληρό work? Is this a comparative form?

Yes. πιο means “more,” and it forms the regular comparative with most adjectives:

σκληρό – “hard, harsh” (neuter)
πιο σκληρό – “harder, more harsh”

So:

Το φως γίνεται πιο σκληρό.
= “The light becomes harder / more harsh.”

Some very common adjectives have special (synthetic) comparatives like καλύτερος (“better”), but for most adjectives you use πιο + adjective.

Why is there a comma before αλλά?

αλλά means “but” and is introducing a contrast between two clauses:

Το πρωί το απαλό φως… με ξυπνάει, αλλά το μεσημέρι το φως γίνεται πιο σκληρό.

In Greek, as in English, you normally put a comma before αλλά when it connects two independent clauses (each with its own subject and verb).
You don’t usually put a comma if it only connects two words or short phrases, e.g.:

όμορφο αλλά ακριβό σπίτι – “beautiful but expensive house” (no comma).

What does από mean in από την μπαλκονόπορτα, and why is μπαλκονόπορτα in that form?

από here means “from,” indicating the source or origin:

από την μπαλκονόπορτα – “from the balcony door”

μπαλκονόπορτα is a feminine noun:

Nominative singular: η μπαλκονόπορτα
Accusative singular: την μπαλκονόπορτα

The preposition από takes the accusative case, so the article and the noun must be in the accusative: από την μπαλκονόπορτα.
Morphologically, it’s a compound: μπαλκόνι (balcony) + πόρτα (door).

Can the word order be changed, for example to Το απαλό φως με ξυπνάει το πρωί?

Yes. Greek word order is quite flexible, especially with clear subjects and objects. All of these are possible and natural, with small differences in emphasis:

Το πρωί το απαλό φως με ξυπνάει. – Emphasis on when it happens (in the morning).
Το απαλό φως με ξυπνάει το πρωί. – Slightly more emphasis on the light as the thing that wakes you.
Το απαλό φως το πρωί με ξυπνάει. – Emphasis on “that soft light in the morning” as a unit.

The version in your sentence foregrounds the time phrase (Το πρωί) and then introduces the subject το απαλό φως.

Why does σκληρό have to agree in gender, number, and case with φως?

In Greek, adjectives must agree with the nouns they modify in:

Gender (masculine / feminine / neuter)
Number (singular / plural)
Case (nominative / accusative / etc.)

Here:

το φως – neuter, singular, nominative (subject)
Adjective “harsh”: σκληρός (m.), σκληρή (f.), σκληρό (n.)

So you must use σκληρό:

το φως είναι / γίνεται σκληρό / πιο σκληρό

If the noun changed, the adjective form would change too, e.g.:

ο ήλιος είναι σκληρός – “the sun is harsh” (masc.)
η λάμπα είναι σκληρή – “the lamp is harsh” (fem.)