Η αδερφή μου στεγνώνει τα μαλλιά της με το πιστολάκι, ενώ εγώ προτιμώ την ξυριστική μηχανή από το ξυράφι.

In normal Greek, the possessive pronoun μου usually comes after the noun: η αδερφή μου = my sister.

Greek often uses:

• article + noun + possessive
• η αδερφή μου
• το σπίτι μου
• οι φίλοι μου

You can move things around for emphasis in some contexts, but the neutral, standard way is η αδερφή μου.

Also, Greek usually keeps the definite article where English would not, so my sister is literally the sister my.

Both forms exist.

• αδερφή is very common in everyday Modern Greek.
• αδελφή is a more conservative/formal form and is also correct.

The same happens with αδερφός / αδελφός for brother.

So a learner should recognize both, but αδερφή is extremely natural in spoken Greek.

It can mean either, depending on context.

στεγνώνει is the present tense, imperfective aspect form of στεγνώνω. In English, that can correspond to:

• dries
• is drying
• dries regularly / usually dries

In this sentence, it most naturally sounds like a habitual present:

• My sister dries her hair with a hair dryer...

But Greek present forms often cover both the simple present and the progressive present, and context tells you which one is meant.

In Greek, μαλλιά is normally used in the plural when talking about the hair on someone’s head.

So:

• τα μαλλιά μου = my hair
• literally: my hairs

This is just a normal difference between Greek and English. Even though English often treats hair as a mass noun, Greek usually uses the plural noun μαλλιά in this meaning.

της here means her.

Greek possessive pronouns like μου, σου, του, της, μας, σας, τους are short unstressed forms that usually come after the noun:

• τα μαλλιά της = her hair
• το βιβλίο μου = my book
• ο φίλος του = his friend

So in this sentence:

• τα μαλλιά της literally = the hair of her
• natural English = her hair

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

So when Greek says:

• με το πιστολάκι

it literally means:

• with the hair dryer

But in English, we often leave out the article in this kind of instrumental phrase:

• with a hair dryer
• with the hairdryer

Greek prefers the article here, and that is completely normal.

με means with.

Here it introduces the instrument/tool used to do something:

• στεγνώνει τα μαλλιά της με το πιστολάκι
• She dries her hair with the hair dryer

This is a very common use of με in Greek:

• γράφω με μολύβι = I write with a pencil
• κόβω με το μαχαίρι = I cut with the knife

So με often corresponds to English with, especially for means or instrument.

πιστολάκι means hair dryer or blow dryer in everyday Greek.

It is a diminutive form related to πιστόλι (pistol/gun), because the object’s shape suggests that image. So literally it looks like a little pistol-like thing, but in normal usage it simply means hair dryer.

It is a very common everyday word.

Here ενώ means while, but more specifically it introduces a contrast:

• ..., ενώ εγώ προτιμώ ...
• ..., while I prefer ...

So in this sentence it works a lot like:

• while
• whereas

It does not only indicate time. It often connects two contrasting ideas:

• He likes coffee, while/whereas I prefer tea.

That is exactly what it is doing here.

That is right: Greek often omits subject pronouns because the verb ending already tells you the person.

For example:

• προτιμώ already means I prefer

So εγώ is not necessary for basic grammar. It is included here for emphasis or contrast:

• while I prefer...

That fits the sentence well because the speaker is contrasting themself with the sister:

• My sister does X, whereas I prefer Y.

So εγώ is there because it is stylistically useful, not because Greek requires it.

This is the Greek pattern for prefer X to Y:

• προτιμώ + thing preferred + από + thing not preferred

So:

• προτιμώ την ξυριστική μηχανή από το ξυράφι
• I prefer the electric shaver to the razor

A very literal breakdown is:

• προτιμώ = I prefer
• την ξυριστική μηχανή = the shaving machine / the electric shaver
• από το ξυράφι = over/from the razor, meaning rather than the razor

So από introduces the item being compared against.

Because the two nouns have different grammatical genders:

• η μηχανή = feminine
• το ξυράφι = neuter

So their articles and adjective forms must match:

• την ξυριστική μηχανή: feminine accusative singular
• το ξυράφι: neuter accusative singular

The adjective ξυριστική agrees with μηχανή, so it also appears in the feminine form.

This is a basic Greek rule: articles and adjectives agree with the noun in gender, number, and case.

Yes, the direct objects in this sentence are in the accusative.

Examples:

• τα μαλλιά της after στεγνώνει
• την ξυριστική μηχανή after προτιμώ
• το ξυράφι after από

You can often tell from the article:

• η = nominative feminine singular
• την = accusative feminine singular
• το = nominative or accusative neuter singular
• τα = nominative or accusative neuter plural

So:

• η αδερφή μου is the subject
• τα μαλλιά της is the object
• την ξυριστική μηχανή is the object of προτιμώ
• το ξυράφι comes after από

Usually, yes.

ξυριστική μηχανή most commonly means an electric shaver / electric razor, while:

• ξυράφι means a razor blade or manual razor

So the contrast in the sentence is natural:

• one option is an electric shaving device
• the other is a traditional razor

That is why προτιμώ την ξυριστική μηχανή από το ξυράφι means I prefer the electric shaver to the razor.