Ο φίλος της δεν έχει πια γενειάδα, γιατί την ξύρισε χτες.

It can mean either her friend or her boyfriend, depending on context.

• ο φίλος = the male friend
• της = her

So literally, Ο φίλος της means her male friend.
But in everyday Greek, ο φίλος μου / σου / της etc. can also mean my boyfriend / your boyfriend / her boyfriend, especially if the context is romantic.

So this phrase is grammatically her friend, but in real usage it may very naturally mean her boyfriend.

της is a genitive weak pronoun, and here it shows possession.

So:

• ο φίλος = the friend
• της = of her / her

Together: ο φίλος της = her friend

This is very common in Greek. Possession is often shown with these short pronoun forms after the noun:

• ο φίλος μου = my friend
• ο φίλος σου = your friend
• ο φίλος της = her friend

Greek uses the definite article much more often than English.

So where English says:

• Her friend no longer has a beard

Greek says:

• Ο φίλος της...

Literally, that is the friend of hers.

This is completely normal Greek. Even when English would not use the, Greek often does.

Here πια means any more / no longer.

So:

• δεν έχει = he doesn't have
• πια = any more / any longer
• γενειάδα = beard

Together:

• δεν έχει πια γενειάδα = he no longer has a beard

A very natural way to understand πια in negative sentences is:

• not ... anymore
• no longer

For example:

• Δεν μένει πια εδώ. = He doesn’t live here anymore.
• Δεν δουλεύει πια εκεί. = She no longer works there.

Because δεν is the normal negation word used before verbs in Greek.

• έχει = he/she has
• δεν έχει = he/she does not have

So:

• Ο φίλος της έχει γενειάδα. = Her friend has a beard.
• Ο φίλος της δεν έχει πια γενειάδα. = Her friend no longer has a beard.

Because Greek often uses a bare noun after έχω when talking about physical features, possessions, or general characteristics.

So:

• έχει γενειάδα = he has a beard

This is natural Greek. You do not need μια here.

You could say έχει μια γενειάδα, but that would sound more specific or descriptive, as if you are drawing attention to the beard itself. In this sentence, the plain statement of appearance is better:

• έχει γενειάδα = has a beard

Similar examples:

• Έχει μακριά μαλλιά. = She has long hair.
• Έχει αυτοκίνητο. = He has a car.
• Έχει αδερφό. = She has a brother.

Yes. Greek often uses both, but they are not exactly the same in feel.

• γενειάδα = beard
• γένια = literally beard hair / facial hair, but often also just beard in everyday speech

So these are both natural:

• Δεν έχει πια γενειάδα.
• Δεν έχει πια γένια.

Very roughly:

• γενειάδα sounds a bit more like a beard as a whole thing
• γένια can sound a bit more like beard/facial hair in a general sense

In many everyday situations, the difference is small.

την refers back to γενειάδα.

• γενειάδα is a feminine singular noun
• the corresponding accusative feminine singular pronoun is την

So:

• την ξύρισε = he shaved it

Literally:

• την = it (referring to the beard)
• ξύρισε = shaved

Greek uses grammatical gender here. Since γενειάδα is feminine, the pronoun must also be feminine.

Because Greek often includes the object pronoun when it is clear and relevant.

• ξύρισε by itself = he shaved or he shaved something
• την ξύρισε = he shaved it

Here the pronoun makes it explicit that what he shaved was the beard.

In English, we often need it too:

• because he shaved it yesterday

So this matches English quite well.

Because weak object pronouns in Greek usually come before the finite verb.

So:

• την ξύρισε = he shaved it
• τον είδα = I saw him
• τη θέλω = I want it / her
• μας ξέρουν = they know us

This word order is standard in modern Greek.

ξύρισε is the aorist form, which here expresses a completed action in the past:

• ξύρισε = he shaved

In this sentence, the idea is that yesterday he performed the action and completed it. That is exactly the kind of thing the Greek aorist is used for.

So:

• γιατί την ξύρισε χτες = because he shaved it yesterday

If Greek used the imperfect here, it would suggest an ongoing or repeated action, which would not fit as well.

Because ξύρισε and ξυρίστηκε are not exactly the same.

• ξύρισε = he shaved it
• ξυρίστηκε = he shaved himself / he got shaved / he shaved

In this sentence, the speaker is specifically talking about the beard as an object:

• την ξύρισε = he shaved it

That is why ξύρισε fits perfectly.

You could also hear:

• Ο φίλος της δεν έχει πια γενειάδα, γιατί ξυρίστηκε χτες.

That would mean:

• Her friend no longer has a beard because he shaved yesterday / because he shaved himself yesterday.

Both are possible, but the original sentence focuses more directly on the beard.

έχει is present tense.

• έχω = I have
• έχει = he/she/it has

So:

• δεν έχει πια γενειάδα = he doesn’t have a beard anymore

The sentence combines:

• a present situation: he no longer has a beard
• with a past reason: because he shaved it yesterday

This is very natural in both Greek and English.

γιατί here means because.

So:

• ... γιατί την ξύρισε χτες. = ... because he shaved it yesterday.

Greek γιατί can mean both:

• why?
• because

The meaning depends on the sentence.

Examples:

• Γιατί έφυγες; = Why did you leave?
• Έφυγα γιατί κουράστηκα. = I left because I got tired.

Because the second part is giving the reason for the first part.

• Ο φίλος της δεν έχει πια γενειάδα = statement
• γιατί την ξύρισε χτες = reason

So the comma helps separate the main statement from the explanation. This is common and natural in written Greek.

χτες means yesterday.

Yes, it is basically the same as χθες.
Both are correct in Modern Greek.

• χτες is very common in everyday language
• χθες is a bit more formal or conservative in spelling

So:

• την ξύρισε χτες = he shaved it yesterday
• την ξύρισε χθες = same meaning

Greek word order is more flexible than English, though not completely free.

The given sentence is very natural:

• Ο φίλος της δεν έχει πια γενειάδα, γιατί την ξύρισε χτες.

But other arrangements are possible, especially for emphasis, for example:

• Ο φίλος της δεν έχει γενειάδα πια, γιατί την ξύρισε χτες.
• Γιατί την ξύρισε χτες, ο φίλος της δεν έχει πια γενειάδα.
  This is possible, but less neutral.

The original version sounds like a normal, natural statement.

Yes, sometimes it can move slightly, though some positions sound more natural than others.

These are both natural:

• δεν έχει πια γενειάδα
• δεν έχει γενειάδα πια

Both mean he no longer has a beard.

The first one may sound a bit more neutral in this sentence, but the difference is small.

A very literal translation would be:

• The friend of hers doesn’t have any longer beard, because he shaved it yesterday.

That is not good natural English, but it helps show the Greek structure:

• Ο φίλος της = the friend of hers
• δεν έχει πια γενειάδα = doesn’t have any longer beard
• γιατί την ξύρισε χτες = because he shaved it yesterday

A natural English translation is:

• Her friend doesn’t have a beard anymore, because he shaved it yesterday.
• or Her friend no longer has a beard because he shaved it yesterday.

A simple pronunciation guide is:

• O FEE-los tis den E-hi pya ye-nya-THA, ya-TI tin KSI-ri-se HTES.

A few notes:

• φ sounds like f
• γ before ε here sounds like a soft y sound, so γενειάδα starts roughly like ye-
• χ is a rough sound, like a harsher h
• ξ sounds like ks
• stress matters:
  • φίλος
  • πια
  • γενειάδα
  • γιατί
  • ξύρισε
  • χτες

If you want, you can think of the rhythm as:

• Ο ΦΙλος της / δεν Εχει πια γενειΑδα / γιατί την ΞΥρισε ΧΤΕΣ

A few important Greek patterns all appear here:

1. Possession with a genitive pronoun

   • ο φίλος της = her friend

2. Negation with δεν

   • δεν έχει = doesn’t have

3. πια = anymore / no longer

   • δεν έχει πια = doesn’t have anymore

4. Object pronoun before the verb

   • την ξύρισε = he shaved it

5. Aorist for a completed past action

   • ξύρισε χτες = shaved yesterday

So this is actually a very useful sentence because it combines several common structures in natural everyday Greek.