Learn Hardcore Latin: Post scholam domum vestram venite, deinde cum aliis amicis ludite. - After school come to your home, then play with the other friends.

The accusative here is required by the preposition post. Many Latin prepositions always take a specific case; post is one of the prepositions that always takes the accusative.

Why is there no preposition in front of domum? Why not ad domum?

With words for home, Latin often uses a special idiom:

domum (accusative) on its own means to home / homewards.

So:

domus = house, home (nominative)
domum = to home, to the house (direction toward home)

Because domum already contains the idea of motion towards home, Latin does not usually add ad. Ad domum is technically possible in some contexts, but the standard, natural way to say go home is domum ite / venite, not ad domum ite.

Why is it domum vestram and not just domum? What is vestram doing, and what case is it?

Vestram is the possessive adjective meaning your (plural) and it agrees with domum:

domum – accusative singular feminine
vestram – accusative singular feminine (to match domum)

So domum vestram means your home (specifically, you all’s home, addressed to more than one person).

The case of vestram is accusative because it must match the noun it modifies (domum, which is accusative). Adjectives in Latin agree with their nouns in gender, number, and case.

Why is it vestram and not tuam?

Latin distinguishes between singular and plural you:

tu = you (one person)
vos = you (more than one person)

The matching possessives are:

tuus, -a, -um = your (belonging to one person)
vester, -tra, -trum = your (belonging to several people)

Here, the commands venite and ludite are addressed to a group (plural), so the possessive must also be plural: vestram (your, plural), not tuam (your, singular).

What forms are venite and ludite, and how do they show that the command is plural?

Both venite and ludite are second person plural imperatives:

venite = come! (you all) – from venio, venire (4th conjugation)
ludite = play! (you all) – from ludo, ludere (3rd conjugation)

Latin imperative endings:

-a / -e / -e (depending on conjugation) for 2nd person singular (one person)
-te for 2nd person plural (more than one person)

So:

veni! = come! (you, singular)
venite! = come! (you all)
lude! = play! (you, singular)
ludite! = play! (you all)

The -te ending marks the plural command.

What does deinde mean, and does it affect the grammar of the sentence?

Deinde is an adverb meaning then, next, afterwards.

It does not govern a case.
It does not change the forms of verbs or nouns.
It simply tells you about the sequence of actions: do one thing, then do another.

So in your sentence, deinde just tells you that the playing with friends comes after coming home. Grammatically, it stands independently and doesn’t require any special construction.

Why is it cum aliis amicis and not cum alios amicos?

The preposition cum normally takes the ablative case and means with (in company):

cum
- ablative = with (someone)

Here:

amicis is ablative plural of amicus (friend).
aliis is ablative plural of alius (other), agreeing with amicis.

So:

cum aliis amicis = with other friends (ablative plural after cum).

Aliōs amicōs would be accusative plural and would be incorrect after cum, because cum requires the ablative.

How do aliis and amicis agree with each other?

In cum aliis amicis:

amicis = ablative plural masculine (friends)
aliis = ablative plural masculine (other)

Latin adjectives (here aliis, “other”) must match the nouns they describe (here amicis, “friends”) in:

gender: both masculine
number: both plural
case: both ablative

So aliis amicis literally means with other [friends]; aliis is describing amicis and therefore copies its grammatical form.

Why is post scholam using scholam (accusative) and not schola (ablative)? I’ve seen time expressions in the ablative.

Latin has several ways to express time:

Preposition + accusative for “after/before [time]”:
- post scholam = after school
- ante cenam = before dinner
Here, post (and ante) require the accusative.
Ablative of time when (no preposition) for “at/on/in [time]”:
- tertia hora = at the third hour
- hieme = in winter

In your sentence, you have the preposition post, which must be followed by the accusative, so scholam is correct. If there were no preposition, then an ablative could be used for “at that time,” but that’s a different construction.

Can the word order be changed? For example, could we say Post scholam venite domum vestram, deinde ludite cum aliis amicis?

Yes, Latin word order is generally more flexible than English, because case endings show who is doing what.

Post scholam venite domum vestram, deinde ludite cum aliis amicis is perfectly understandable and grammatical.
The main constraints are:
- prepositions must stay with their objects (post scholam, cum aliis amicis);
- domum usually stays close to what describes whose home it is (domum vestram).

Otherwise, verbs, adverbs like deinde, and phrases like domum vestram can move around without changing the basic meaning, though different orders can sound more or less natural or emphatic.

What nuance does venite domum vestram have compared to something like ite domum vestram?

Both venite and ite are plural imperatives:

venite – come! (plural)
ite – go! (plural)

Subtle difference:

venire (to come) often implies coming towards the speaker or to a place associated with the speaker.
ire (to go) is more neutral: simply go from one place to another.

In everyday classroom or parental talk, venite domum vestram can still be used as a general “come home” (to your home), functioning very much like “go home” in English. Latin isn’t always as strict here in commands; context matters. But if you wanted to be closer to English Go home, ite domum vestram would be the direct equivalent.

Does post scholam refer to leaving the building or just the time after school is over?

Post scholam is primarily a time expression: after school (is over).

It does not explicitly say whether this is:

after leaving the physical building, or
after the lessons/time of school has finished.

Like English “after school,” it is somewhat vague and can cover both ideas. If you wanted to focus on physically coming out of the school building, Latin might prefer something like ex schola (out of/from the school) plus a time indication, but post scholam is a natural way to refer to the time after school.

Could we say aliis cum amicis instead of cum aliis amicis?

Grammatically, aliis cum amicis is not wrong, because cum with the ablative can sometimes appear after its noun as an enclitic (e.g., amicis cum). But:

The normal, straightforward order in prose is cum
- ablative: cum aliis amicis.
Putting aliis first and moving cum after it (aliis cum amicis) is unusual and stylistically marked; it might sound poetic or forced in many contexts.

For learners, it is best to stick with the classical prose pattern: cum aliis amicis.