Στον λογαριασμό μου εμφανίστηκε μια μικρή χρέωση που δεν κατάλαβα.

Στον is a contraction of σε + τον.

• σε is a very common preposition that can mean in, on, at, to, depending on context
• τον is the masculine singular accusative article, meaning the

So στον λογαριασμό literally comes from σε τον λογαριασμό and means something like in/on the account. In this sentence, the natural English meaning is on my account or in my account, not necessarily a literal to my account.

The dictionary form is ο λογαριασμός.

Here, the noun is after σε, and in Modern Greek σε takes the accusative. So:

• nominative: ο λογαριασμός
• accusative: τον λογαριασμό

That is why you see λογαριασμό instead of λογαριασμός.

In Greek, the weak possessive pronouns such as μου, σου, του, της usually come after the noun:

• ο λογαριασμός μου = my account
• η κάρτα μου = my card

So στον λογαριασμό μου is the normal way to say in/on my account.

If you want stronger emphasis, Greek often uses δικός:

• ο δικός μου λογαριασμός = my own account

But in your sentence, the simple μου is the standard choice.

Εμφανίστηκε is the aorist, 3rd person singular form of εμφανίζομαι, which often means:

• appear
• show up
• come up

So here it means appeared or showed up.

It has a middle/passive-looking form, but the meaning here is not really a true passive like was shown. It behaves more like an intransitive verb:

• Μια χρέωση εμφανίστηκε = A charge appeared

Compare:

• Η εφαρμογή εμφάνισε μια χρέωση = The app displayed a charge
• Μια χρέωση εμφανίστηκε = A charge appeared

So the form is passive-looking, but the meaning is more like appeared.

Greek word order is much more flexible than English word order.

This sentence starts with the location phrase:

• Στον λογαριασμό μου = On my account

Then comes the verb:

• εμφανίστηκε

Then the subject:

• μια μικρή χρέωση

This is very natural in Greek when introducing new information. It has a presentational feel, similar to English sentences like:

• There appeared a small charge on my account
• A small charge showed up on my account

You could also say:

• Μια μικρή χρέωση εμφανίστηκε στον λογαριασμό μου

That is also grammatical, but the original version sounds very natural and smooth.

Because χρέωση is a feminine singular noun, both the article and the adjective must agree with it.

• μια = feminine singular indefinite article, a
• μικρή = feminine singular form of small
• χρέωση = feminine singular noun, charge

So:

• μια μικρή χρέωση = a small charge

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

Compare:

• ένας μικρός λογαριασμός = a small account
• μια μικρή χρέωση = a small charge
• ένα μικρό ποσό = a small amount

Not exactly.

Χρέωση usually means a charge, debit, or billing entry. In a banking or card context, it is something that was charged to your account.

It is related to χρεώνω, meaning to charge.

It is not quite the same as χρέος, which means debt.

So in this sentence, χρέωση is the right word for a small amount that appeared on an account or card statement.

Yes. Here που introduces a relative clause and means that or which:

• μια μικρή χρέωση που δεν κατάλαβα
• a small charge that I didn’t understand

A useful thing for learners is that που does not change form. Unlike English, where you may think about who, which, that, Greek very often just uses που for all of these in everyday language.

A more formal alternative would be something like:

• μια μικρή χρέωση την οποία δεν κατάλαβα

But that sounds more formal and heavier. Που is the normal everyday choice.

Because που already links back to χρέωση.

In English, you might mentally expect something like that I didn’t understand it, but English also drops the extra it in standard usage. Greek does the same here:

• χρέωση που δεν κατάλαβα = charge that I didn’t understand

You normally do not add την here in standard Greek, because the relative connection is already doing the job.

So the clause is complete as it is.

Κατάλαβα is the aorist form of καταλαβαίνω and means I understood or, with negation, I didn’t understand.

The Greek aorist is often used for a single completed event. Here the speaker means that they saw the charge and did not understand it at that moment.

So:

• δεν κατάλαβα = I didn’t understand
• δεν καταλάβαινα would mean something more like I wasn’t understanding or I used not to understand

In this sentence, the aorist is the natural choice because the speaker is referring to one specific charge and one specific moment of confusion.

Because δεν is the normal negation for the indicative, including ordinary past tense statements.

• δεν κατάλαβα = I didn’t understand

Μη(ν) is used with:

• the subjunctive
• commands
• certain fixed expressions

So here, since κατάλαβα is a regular past indicative form, δεν is the correct negative word.

They are the same word.

Both can mean:

• the indefinite article a
• the number one

In everyday writing, μια is very common for the article. The spelling μία is often used when someone wants to show the full stressed form clearly, especially when meaning one rather than just a.

In your sentence, μια μικρή χρέωση simply means a small charge, so μια is completely normal.

Not very naturally.

If you translate each piece too literally, you might get something like:

• On my account appeared a small charge that I didn’t understand

That is understandable, but not natural English.

This sentence is a good reminder that Greek and English organize information differently:

• Greek is comfortable with location + verb + subject
• English usually prefers subject + verb, or something like There was / There appeared

So when reading Greek, it is better to understand the structure rather than force a word-for-word English order.