Sine concordia civitas firma manere non potest.

Because sine is a preposition that takes the ablative. So sine concordia means without harmony / without concord.

This is something you simply learn with the preposition:

• sine + ablative = without

So:

• concordia = nominative singular
• concordiā = ablative singular

In normal spelling, the long vowel is often not marked, but the form here is ablative because sine requires it.

Civitas is nominative singular because it is the subject of the sentence.

The verb phrase is manere non potest = is not able to remain, so the thing that is not able to remain is civitas.

A learner may be tempted to connect civitas with concordia, but they are doing different jobs:

• sine concordia = prepositional phrase, giving a condition
• civitas = subject

Because firma agrees with civitas.

In Latin, adjectives must agree with the nouns they describe in:

• gender
• number
• case

Here:

• civitas is feminine
• singular
• nominative

So the adjective must also be:

• feminine
• singular
• nominative

That gives firma.

Even though a word like civitas does not end in -a, it is still a feminine noun.

Firma is a predicate adjective used with manere.

The idea is not just a firm state as a simple noun phrase, but rather the state cannot remain firm.

So:

• civitas firma can look like a firm state
• but with manere, the sense is to remain firm

This is similar to English:

• The city remains strong
• The city cannot remain strong

Latin often uses verbs like esse, manere, vidēri, and similar verbs with a predicate adjective.

Because it depends on potest.

Potest means is able / can, and verbs of being able are commonly followed by an infinitive in Latin.

So:

• potest manere = can remain
• non potest manere = cannot remain

This is very similar to English:

• can remain
• is able to remain

So the structure is:

• civitas = subject
• non potest = finite verb
• manere = complementary infinitive

Because non negates the verb phrase.

Here it is negating potest:

• potest = can
• non potest = cannot

That is the most natural way to express the negation here.

Latin word order is flexible, so non does not always have to stand in exactly the same position as in English, but placing it before the verb is very common.

Because manere already carries the idea needed: to remain.

Latin often says something like:

• civitas firma manet = the state remains firm

It does not need an extra to be in the way English sometimes builds phrases.

So firma is linked directly to civitas through manere, not through a separate est.

It depends on context.

Civitas can mean several related things, such as:

• state
• community
• body politic
• sometimes city-state
• sometimes citizenship in other contexts

In a sentence like this one, state or community is often the best choice, because the sentence is about political or social stability.

So a learner should not assume civitas always means exactly the same thing in every passage.

Because Latin relies much more on inflection than English does.

English often depends heavily on word order to show who is doing what. Latin shows grammatical relationships through endings, so the order can be rearranged for style, emphasis, or rhythm.

In this sentence:

• sine concordia comes first, which emphasizes the condition without harmony
• civitas then gives the subject
• firma manere gives the idea remain firm
• non potest closes the sentence with the main verbal idea cannot

A more English-like order would be something like:

• Civitas sine concordia firma manere non potest

But the given order is perfectly natural Latin.

No. Firma here is an adjective, not an adverb.

Why?

• It agrees with civitas
• It is nominative feminine singular
• It describes the state itself, not the manner of remaining

If Latin wanted an adverb like firmly, it would use an adverbial form, not firma.

So the meaning is:

• the state cannot remain firm not
• the state cannot remain firmly

A learner often wants to know how to look each word up. The dictionary forms are:

• sine = preposition meaning without
• concordia, concordiae = harmony, concord
• civitas, civitatis = state, community, citizenship
• firmus, firma, firmum = firm, strong, stable
• maneo, manere, mansi, mansum = remain
• possum, posse, potui = be able, can
• non = not

This is especially useful because some forms in the sentence are not the exact headword form:

• concordia here is ablative in function after sine
• potest comes from possum
• firma comes from firmus

Because possum is the standard Latin verb for to be able.

So:

• potest literally means is able
• in natural English, that often becomes can

Both are good ways to understand it:

• civitas firma manere non potest = the state cannot remain firm
• or more literally, the state is not able to remain firm

A common classroom pronunciation would be something like:

SEE-neh con-COR-dee-ah KEE-wi-tahs FEER-mah mah-NEH-reh non POH-test

If using a more restored classical pronunciation, roughly:

SI-ne kon-KOR-di-a KI-wi-tas FIR-ma ma-NE-re non PO-test

A few helpful points:

• c is always hard, like k
• v in classical pronunciation sounds like w
• ae is not present here, so nothing tricky there
• the stress falls on -cor- in concordia
• on -wi- in civitas
• on -ne- in manere
• on the first syllable of potest

That would change the meaning.

Compare:

• civitas firma est = the state is firm
• civitas firma manet = the state remains firm
• civitas firma manere non potest = the state cannot remain firm

So manere adds the idea of continuing in that condition. It is not just about being firm at one moment, but about staying firm.

That nuance is important in the sentence.