Learn Hardcore Greek: Η γιαγιά μου αγαπάει τα γράμματα, γιατί δεν έχει ίντερνετ και πηγαίνει συχνά στο ταχυδρομείο. - My grandmother loves letters because she doesn't have internet and often goes to the post office.

Many verbs end in -άω (αγαπάω, ρωτάω, περνάω).
- In writing, especially more formal, you often see the short form: αγαπώ.
- In everyday speech you hear the long form: αγαπάω.
In the 3rd person singular, both:
- αγαπάει and
- αγαπά
  are correct and mean she loves.

In modern spoken Greek, αγαπάει is very common and sounds completely natural. Αγαπά sounds a bit more formal or literary, but is also correct. You would never use αγαπώ here, because that is 1st person (I love).

What exactly does τα γράμματα mean here? Is it “letters of the alphabet” or “letters you send in the mail”?

Τα γράμματα can mean both, depending on context:

Letters of the alphabet / literacy
- ξέρω τα γράμματα – I know my letters / I am literate.
Letters you send in the mail
- Μου έστειλε δύο γράμματα – He/She sent me two letters.

In this sentence, because the grandmother goes often to the post office, τα γράμματα clearly means letters (that you send and receive by post).

Grammar-wise:

το γράμμα – the letter (singular, neuter)
τα γράμματα – the letters (plural, neuter)

Γιατί can mean both why and because. How do I know which meaning it has here?

You know from the type of sentence and the position of γιατί.

In questions, at the beginning (often with a question mark), γιατί = why:
- Γιατί δεν έχει ίντερνετ; – Why doesn’t she have internet?
In statements, usually after a comma or another clause, γιατί = because:
- Η γιαγιά μου αγαπάει τα γράμματα, γιατί δεν έχει ίντερνετ.
  – My grandmother loves letters, because she doesn’t have internet.

So:

Question + γιατί → why
Statement + γιατί + reason → because

Why is it Η γιαγιά μου and not η μου γιαγιά, like in English my grandmother?

In Greek, the usual order for possessives is:

article + noun + weak possessive pronoun

Examples:

ο αδελφός μου – my brother
η μητέρα σου – your mother
το παιδί του – his child

So η γιαγιά μου is the normal way to say my grandmother.

Forms like η μου γιαγιά are archaic / poetic and not used in everyday modern Greek. If you want to emphasize my, you use δικός / δική / δικό:

η δική μου γιαγιά – my own grandmother (with emphasis on my)

Why do we say δεν έχει ίντερνετ and put δεν before έχει?

In Greek, the standard negation for verbs is δεν placed directly before the verb:

έχει ίντερνετ – she has internet
δεν έχει ίντερνετ – she does not have internet

You cannot move δεν after the verb; it always comes before it.

In informal speech and writing, δεν can appear as δε when the next word starts with a consonant:

δε(ν) έχει ίντερνετ

This δε / δεν is like English not / don’t / doesn’t, but it is always separate and always before the verb in simple sentences.

Why doesn’t ίντερνετ have an article here? Could I also say δεν έχει το ίντερνετ?

Ίντερνετ in Greek is usually treated like an uncountable, mass noun (like water, electricity):

δεν έχει ίντερνετ – she does not have internet (connection / access)

We often drop the article with such nouns when we mean them in general.

You can say:

το ίντερνετ – the internet (as a thing, more like the English technical term)
δεν έχει ίντερνετ στο σπίτι της – she doesn’t have internet at her house

But δεν έχει το ίντερνετ on its own sounds odd or unfinished, like:

she doesn’t have the internet (which suggests a specific internet, not the general service).

Grammar notes:

το ίντερνετ is grammatically neuter singular, but the noun itself is indeclinable (it stays ίντερνετ in all cases).
A more formal Greek word is το διαδίκτυο.

What is the difference between πηγαίνει and πάει? Could I say … και πάει συχνά στο ταχυδρομείο?

Both πηγαίνει and πάει mean he/she/it goes.

πηγαίνει – 3rd person singular of πηγαίνω
πάει – 3rd person singular of πάω (shorter, very common spoken form)

In this sentence you can say either:

… γιατί δεν έχει ίντερνετ και πηγαίνει συχνά στο ταχυδρομείο.
… γιατί δεν έχει ίντερνετ και πάει συχνά στο ταχυδρομείο.

They mean the same. Πάει sounds a bit shorter / more casual, but both are fully correct in modern Greek.

Where can I put συχνά in the sentence? Is συχνά πηγαίνει στο ταχυδρομείο also correct?

Yes, συχνά πηγαίνει στο ταχυδρομείο is also correct.

Common positions for συχνά (often) are:

Πηγαίνει συχνά στο ταχυδρομείο.
Συχνά πηγαίνει στο ταχυδρομείο.
Πηγαίνει στο ταχυδρομείο συχνά. (less common, but possible)

All three are grammatical. The differences are small and mostly about emphasis:

Πηγαίνει συχνά στο ταχυδρομείο – neutral, the most typical word order.
Συχνά πηγαίνει στο ταχυδρομείο – lightly emphasizes how often (often, she goes to the post office).
Πηγαίνει στο ταχυδρομείο συχνά – a bit more marked; the adverb sounds like an afterthought or extra comment.

What exactly is στο in στο ταχυδρομείο? Is it one word or two?

Στο is a contraction of two words:

σε + το → στο

σε = in, at, to (a very common preposition)
το = the (neuter singular definite article)

So:

σε το ταχυδρομείο → στο ταχυδρομείο – to the / at the post office

This contraction happens very regularly:

σε + τον → στον (στον φίλο μου – to my friend)
σε + την → στην (στην πόλη – in the city)
σε + το → στο (στο σπίτι – at home)

Why is there a comma before γιατί in this sentence? Is it always required?

In this sentence, the comma separates the main statement from the reason:

Η γιαγιά μου αγαπάει τα γράμματα,
– My grandmother loves letters,
γιατί δεν έχει ίντερνετ…
– because she doesn’t have internet…

In Greek, you often use a comma before γιατί when it introduces a separate explanatory clause, just like in English:

Δεν βγήκα, γιατί έβρεχε. – I didn’t go out, because it was raining.

When γιατί is more tightly connected to the verb and the reason is very short, some writers omit the comma; in many everyday cases, both with and without comma are acceptable, depending on style and the pause you want to indicate.

So:

The comma here is natural and correct.
It is not absolutely mandatory in every sentence with γιατί, but it is very common when the second part clearly explains the first.