Ο μάρτυρας περιέγραψε το συμβάν και τον υπαίτιο του περιστατικού.

Greek often uses the definite article where English might or might not use the.

• ο = the for a masculine singular noun in the nominative case
• μάρτυρας = witness

So Ο μάρτυρας means the witness.

In a full sentence, Greek usually includes the article when talking about a specific person or thing, so leaving it out here would sound less natural unless the context strongly called for it.

Ο μάρτυρας is in the nominative case, because it is the subject of the sentence — the person doing the action.

You can tell from the article:

• ο = masculine singular nominative

So:

• Ο μάρτυρας = the witness as subject

The verb περιέγραψε shows what the witness did.

Περιέγραψε is the aorist form of περιγράφω.

Here it means:

• he described
• or more generally described

The aorist is commonly used for a completed action in the past. It does not focus on duration; it just presents the action as a whole.

So:

• Ο μάρτυρας περιέγραψε... = The witness described...

They are different because they are different genders, even though both are direct objects.

Both are in the accusative case, because they are the things the witness described.

• το συμβάν
  
  • το = neuter singular accusative/nominative article
  • συμβάν = neuter noun
• τον υπαίτιο
  
  • τον = masculine singular accusative article
  • υπαίτιο = masculine singular accusative form of υπαίτιος

So the difference is not in their function — both are objects — but in their gender.

Because τον υπαίτιο is a direct object, so it must be in the accusative case.

Compare:

• ο υπαίτιος = the culprit / the responsible person as subject
• τον υπαίτιο = the culprit / the responsible person as object

In this sentence, the witness described the culprit, so Greek uses the accusative:

• περιέγραψε τον υπαίτιο = described the culprit

It is originally an adjective, meaning something like responsible or guilty, but here it is being used as a noun.

So:

• ο υπαίτιος literally means the responsible one
• in natural English, that usually becomes the culprit or the person responsible

This is common in Greek: an adjective can function like a noun when the meaning is clear.

Του περιστατικού is in the genitive case and means:

• of the incident

It tells you what the culprit is responsible for:

• τον υπαίτιο του περιστατικού = the person responsible for the incident
• literally: the culprit of the incident

So the genitive phrase modifies υπαίτιο.

Yes, they are very close in meaning.

• συμβάν = event, occurrence, sometimes incident
• περιστατικό = incident, case, occurrence

In this sentence, using both can sound a bit formal, legal, or report-like. Greek often allows this kind of near-synonymous wording, especially in official or descriptive contexts.

So the sense is:

• the witness described the event itself
• and the person responsible for that incident

Even though the two nouns overlap, they are not necessarily felt as a mistake; it can just be a formal style.

Yes. A simpler version could be:

• Ο μάρτυρας περιέγραψε το περιστατικό και τον υπαίτιο.
• Ο μάρτυρας περιέγραψε το συμβάν και τον υπαίτιο.

These would sound more streamlined.

The original sentence is still understandable, but it has a slightly more bureaucratic or formal tone because of the pair συμβάν / περιστατικό.

Because Greek often uses the genitive where English uses of or sometimes a phrase like responsible for.

Literally:

• τον υπαίτιο του περιστατικού = the culprit of the incident

But natural English usually says:

• the person responsible for the incident
• the culprit in the incident

So Greek does not need a separate word equivalent to English for here.

Yes, Greek word order is more flexible than English because case endings and articles show grammatical roles.

The neutral order here is:

• Ο μάρτυρας περιέγραψε το συμβάν και τον υπαίτιο του περιστατικού.

But Greek could change the order for emphasis, for example:

• Το συμβάν και τον υπαίτιο του περιστατικού περιέγραψε ο μάρτυρας.

This still means the same thing, but it emphasizes what was described rather than who described it.

Not necessarily in meaning, though it often behaves grammatically like a masculine noun in this form.

In this sentence:

• ο μάρτυρας = a male witness, or a generic the witness

But μάρτυρας can also refer to a female witness, often with:

• η μάρτυρας

So the noun itself can refer to either sex, while the article helps show gender in context.

A very useful way is:

• Ο μάρτυρας = the witness
• περιέγραψε = described
• το συμβάν = the event / incident
• και = and
• τον υπαίτιο του περιστατικού = the person responsible for the incident

So the structure is:

• Subject: Ο μάρτυρας
• Verb: περιέγραψε
• Object 1: το συμβάν
• Object 2: τον υπαίτιο του περιστατικού

This kind of chunking is especially helpful in Greek because articles and case endings show how the parts fit together.