Orator in rostris stans cives clara voce appellat.

Latin word order is much more flexible than English word order because the endings show what each word is doing.

In this sentence:

• orator = subject
• cives = direct object
• appellat = main verb

A very literal rearrangement into a more English-like order would be:

• Orator appellat cives clara voce
• The speaker addresses the citizens in a clear voice

Latin often puts the verb near the end, and it can place descriptive phrases like in rostris stans before the object. So the original order is perfectly natural Latin.

Orator is a masculine noun meaning speaker or orator.

Here it is in the nominative singular, which tells you it is the subject of the sentence: the person doing the action.

So:

• orator = the speaker

In rostris means on the rostra or on the speaker’s platform.

A few important points:

• in
  • ablative often means in or on, expressing location.
• rostris is the ablative plural of rostra.

Why plural? Because rostra is the regular Latin name for the public speaking platform in the Roman Forum. Historically, the word is connected with ship prows or beaks, and the platform got its name from captured ship-prows displayed there. Even when it refers to one platform, Latin commonly uses the plural form rostra.

So in rostris is just the standard idiomatic way to say on the rostra.

Stans is the present active participle of sto, stare, meaning standing.

It agrees with orator:

• orator = nominative singular masculine
• stans = nominative singular, matching the subject

So orator in rostris stans means:

• the speaker, standing on the rostra
• or more smoothly, the speaker standing on the rostra

It adds extra information about the speaker while the main action is still carried by appellat.

Because stans is not a finite verb here. It is a participle, not the main verb.

Latin often uses participles where English might use:

• a relative clause: the speaker who is standing
• or a simpler phrase: the speaker standing

The only finite verb in the sentence is appellat = addresses.

So the structure is:

• orator ... stans = the speaker standing ...
• appellat = addresses

Cives is the accusative plural here, and it is the direct object of appellat.

So it answers the question:

• whom does the speaker address?
• cives = the citizens

Why not nominative plural? Because the sentence already has a clear singular subject, orator, and appellat is third person singular. That makes cives the object, not another subject.

Appellat is from appello, appellare.

Here it means something like:

• addresses
• calls to
• calls upon

Its form is:

• present tense
• active voice
• indicative mood
• third person singular

So appellat = he/she addresses, and in this sentence:

• the speaker addresses the citizens

Clara voce is in the ablative singular:

• clara = ablative singular feminine
• voce = ablative singular feminine of vox, vocis = voice

Together it means:

• with a clear voice
• in a clear voice

This is an ablative phrase expressing means or manner.

So the idea is:

• the speaker addresses the citizens with/in a clear voice

That is normal. Latin often uses the ablative of manner without cum when the noun has an adjective.

Compare the general pattern:

• cum voce = with a voice
• clara voce = with a clear voice

When there is a descriptive adjective like clara, Latin very often omits cum. So clara voce is exactly what you would expect.

No. The forms do not match.

• clara = ablative singular feminine
• voce = ablative singular feminine
• cives = accusative plural here

Adjectives in Latin agree with the nouns they describe in gender, number, and case. Since clara matches voce, those two belong together.

So:

• clara voce = with a clear voice

not

• clear citizens

Because in can take either the ablative or the accusative, depending on the meaning.

• in + ablative = location, in/on
• in + accusative = motion into/toward

Here the speaker is already located on the platform, not moving onto it, so Latin uses the ablative:

• in rostris = on the rostra

If it meant onto the rostra, you would expect in rostra with the accusative.

In a sense, both.

A participle is a verbal adjective:

• it behaves like an adjective because it agrees with a noun
• it behaves like a verb because it comes from a verb and keeps verbal meaning

So stans:

• agrees with orator
• still has the verbal sense standing

That is why orator ... stans means the speaker standing...

Yes. You could say:

• Orator in rostris cives clara voce appellat.

That would still mean:

• The speaker on the rostra addresses the citizens in a clear voice, or
• The speaker addresses the citizens from the rostra in a clear voice

Adding stans makes the picture more vivid by explicitly saying that he is standing there.

A very literal translation would be:

• The speaker, standing on the rostra, addresses the citizens with a clear voice.

A smoother English version might be:

• Standing on the rostra, the speaker addresses the citizens in a clear voice.
• The speaker on the rostra addresses the citizens clearly.

The exact English wording can vary, but the Latin grammar stays the same.