Post cenam parentes cum filiis et filiabus longum sermonem de vita bona habent.

Because post is a preposition that takes the accusative case when it means after.

So:

• cena = dinner, supper
• cenam = dinner/supper in the accusative singular

Therefore post cenam means after dinner.

This is a standard pattern in Latin:

• post bellum = after the war
• post urbem conditam = after the city was founded

Do not confuse this with postquam, which is a conjunction meaning after and introduces a clause, not a noun phrase.

Because they follow the preposition cum, which means with, and cum takes the ablative case.

So:

• filius → filiis = with sons
• filia → filiabus = with daughters

That gives:

• cum filiis et filiabus = with sons and daughters

This is one of the first very common case patterns Latin learners meet:

• cum amico = with a friend
• cum amicis = with friends

Parentes is nominative plural, and it is the subject of habent.

You know it is the subject because:

1. The verb habent is third person plural = they have
2. Parentes fits as a plural noun meaning parents
3. The rest of the sentence contains objects or prepositional phrases

So the basic structure is:

• parentes = the parents
• habent = have

Together: the parents have

Although parentes can also look like accusative plural in some contexts, here the verb and sentence structure show that it is nominative.

Sermonem is the direct object of habent.

The verb habere usually means to have, so whatever is being had is put in the accusative:

• sermo = conversation, discussion
• sermonem = conversation/discussion as the object

Longum is an adjective modifying sermonem, so it must agree with it in:

• gender: masculine
• number: singular
• case: accusative

That is why both are accusative singular masculine:

• longum sermonem = a long conversation

Latin adjectives agree with the nouns they describe, even if the word order changes.

Because the preposition de takes the ablative case.

So:

• vita = life
• vita bona = good life, in the ablative
• vitam bonam would be accusative, which would be wrong after de

Thus:

• de vita bona = about the good life

This is another standard Latin pattern:

• de amico = about the friend
• de bello = about the war
• de re publica = about the republic/state

In normal Latin spelling, long vowels are often not marked, so bona can stand for bonā in a textbook that does not use macrons consistently.

Grammatically, the form here is ablative singular feminine, agreeing with vita:

• vita = ablative singular feminine
• bona = ablative singular feminine

So de vita bona means about a good life or about the good life.

If macrons were shown, many books would write:

• de vītā bonā

But without macrons, it is simply written de vita bona.

Yes. In Latin, habere sermonem is a natural way to say to have a conversation or to hold a conversation.

So although habere often means simply to have, it can also be used in expressions like this, much like English:

• have a conversation
• have a discussion

Thus:

• longum sermonem habent = they have a long conversation / they hold a long discussion

This is perfectly normal idiomatic Latin.

Latin word order is much more flexible than English word order because Latin shows grammatical function mainly through endings, not position.

In English, word order is crucial:

• The parents have a conversation
• A conversation has the parents would mean something different or sound wrong

In Latin, endings show what each word is doing:

• parentes = subject
• sermonem = object
• habent = verb

So the sentence can place words in an order that sounds natural or emphasizes certain ideas:

• Post cenam comes first to set the scene: after dinner
• parentes comes early as the topic
• cum filiis et filiabus adds who they are with
• longum sermonem builds toward the object
• habent finishes the thought

Latin often puts the verb near the end, but not always. Flexibility is normal.

It is simply being more specific: sons and daughters.

Latin certainly does have more general words, for example:

• liberi = children

So a Latin sentence could have said something like:

• cum liberis = with their children

But cum filiis et filiabus explicitly includes both male and female children. This can be done for clarity, fullness, or style.

It also helps a learner notice the different plural ablative endings:

• -is in filiis
• -abus in filiabus

Because first-declension nouns like filia sometimes use -abus in the dative and ablative plural to avoid confusion with similar masculine forms.

So:

• filiis = to/for/with sons
• filiabus = to/for/with daughters

This is especially common when both masculine and feminine forms appear together, as here:

• cum filiis et filiabus

It helps distinguish:

• sons from daughters
• masculine from feminine

You may also see this with:

• deis et deabus = gods and goddesses
• liberis et liberabus is much less common because liberi/liberae behave differently in meaning and use, but the same principle of distinction exists in some noun pairs

It can mean several related things, depending on context.

Common meanings include:

• conversation
• talk
• discussion
• speech
• style of speech
• language in some contexts

In this sentence, longum sermonem de vita bona habent, the meaning is clearly a long conversation/discussion about the good life.

So learners should remember that Latin nouns often have a range of meanings rather than one exact English equivalent.

Either can work, depending on context.

Latin has no definite or indefinite article, so vita bona can mean:

• a good life
• the good life
• sometimes even good living, depending on style and context

Since the meaning has already been given to the learner, the important grammatical point is that:

• vita is ablative singular after de
• bona agrees with vita

So the phrase means they are talking about good life / about the good life / about a good life, with English wording chosen by context.

A learner often needs to work backward from the forms in the sentence to the dictionary entries. Here they are:

• post → post = after
• cenam → cena, cenae = dinner, supper
• parentes → parens, parentis = parent
• cum → cum = with
• filiis → filius, filii = son
• filiabus → filia, filiae = daughter
• longum → longus, longa, longum = long
• sermonem → sermo, sermonis = conversation, talk
• de → de = about, concerning
• vita → vita, vitae = life
• bona → bonus, bona, bonum = good
• habent → habeo, habere, habui, habitum = have

This is a very useful skill in Latin: recognizing an inflected form and identifying its dictionary form.