Ο γιος της φίλης μου είναι πολύ ζωηρός, αλλά η κόρη της είναι πιο φρόνιμη.

Because Greek uses the genitive to show possession.

• η φίλη μου = my friend
• της φίλης μου = of my friend / my friend’s

So in Ο γιος της φίλης μου, the phrase literally works like the son of my friend.

φίλη is the basic dictionary form, while φίλης is the genitive singular form.

μου means my.

In Greek, short possessive words like μου (my), σου (your), της (her) usually come after the noun:

• η φίλη μου = my friend
• ο γιος μου = my son

So της φίλης μου is literally of the friend my, but in natural English it means of my friend.

They look the same, but they are doing different jobs.

1. In της φίλης μου, της is the genitive feminine singular article: of the
2. In η κόρη της, της is the possessive pronoun: her

So:

• της φίλης μου = of my friend
• η κόρη της = her daughter

Same form, different function.

Greek normally uses the definite article much more than English does.

So Greek says:

• ο γιος = the son
• η κόρη = the daughter

Even when possession is shown, the article usually stays:

• ο γιος της φίλης μου
• η κόρη της

This is completely normal Greek structure.

Because adjectives in Greek must agree with the noun they describe in gender, number, and case.

• ο γιος is masculine singular, so: ζωηρός
• η κόρη is feminine singular, so: φρόνιμη

This is very common in Greek:

• καλός for a masculine noun
• καλή for a feminine noun
• καλό for a neuter noun

ζωηρός means something like lively, energetic, or full of life.

When talking about a child, it can be positive or slightly negative depending on context:

• positive: active, lively
• less positive: boisterous, a bit too energetic

Because it is contrasted here with φρόνιμη, it may suggest that the boy is a bit more rowdy or hard to manage, not just cheerful.

φρόνιμη often means well-behaved, sensible, or obedient, especially for a child.

It does not just mean smart in the academic sense.

So here πιο φρόνιμη most likely means:

• better behaved
• more sensible
• more obedient

depending on context.

πολύ here means very.

It is an adverb modifying the adjective:

• πολύ ζωηρός = very lively

So:

• είναι πολύ ζωηρός = he is very lively

Greek commonly forms the comparative with πιο + adjective.

So:

• φρόνιμη = well-behaved / sensible
• πιο φρόνιμη = more well-behaved / more sensible

This is a very common and natural pattern in modern Greek.

There is also a more traditional one-word comparative form in many cases, but πιο + adjective is extremely common and often the easiest pattern for learners.

Because Greek can leave than unstated when the comparison is obvious from context.

Here, η κόρη της είναι πιο φρόνιμη means her daughter is more well-behaved, with the comparison understood from the previous clause: more well-behaved than the son.

If Greek wants to state it explicitly, it can use από:

• Η κόρη της είναι πιο φρόνιμη από τον γιο.

But in your sentence, the comparison is clear without it.

Because short possessive pronouns in Greek usually come after the noun:

• η κόρη της = her daughter
• ο αδελφός μου = my brother
• το σπίτι τους = their house

This is the normal Greek pattern.

It refers back to της φίλης μου.

So the meaning is:

• the son of my friend
• but her daughter

In other words, both children belong to my friend.

Greek often relies on context like this, and here the reference is very natural and clear.

Greek word order is more flexible than English, but the given version is the most neutral and natural.

Ο γιος της φίλης μου είναι πολύ ζωηρός, αλλά η κόρη της είναι πιο φρόνιμη.

This order clearly sets up a contrast:

• first the son
• then the daughter
• linked by αλλά = but

You can move things around for emphasis, but this version is standard and easy to understand.

Because each clause has its own subject and predicate:

• Ο γιος της φίλης μου είναι πολύ ζωηρός
• αλλά η κόρη της είναι πιο φρόνιμη

Repeating είναι is the normal, complete way to say it. Greek can sometimes omit repeated words in certain contexts, but here keeping είναι in both clauses sounds natural and standard.

Not exactly. A more literal breakdown would be:

• Ο γιος της φίλης μου = The son of my friend
• είναι πολύ ζωηρός = is very lively
• αλλά = but
• η κόρη της = her daughter
• είναι πιο φρόνιμη = is more well-behaved / sensible

So Greek uses:

• articles more often
• the genitive for possession
• postposed possessive pronouns like μου and της

The overall meaning matches English well, but the structure is distinctly Greek.