Mater dicit se negotium breve in foro habituram esse, sed mox domum redituram esse.

This is an indirect statement in Latin, often called the accusative-and-infinitive construction.

After a verb of saying, thinking, knowing, hearing, etc., Latin often does not use that + a finite verb the way English does. Instead, it uses:

• a subject in the accusative
• plus an infinitive

So here:

• Mater dicit = Mother says
• se ... habituram esse = that she will have ...
• (se) ... redituram esse = that she will return ...

That is why you do not see a normal finite verb like habebit or redibit inside the reported statement.

Se is the reflexive pronoun in the accusative singular, and here it means herself or, more naturally in English, she.

In an indirect statement, the subject of the infinitive is put in the accusative, so se is serving as the subject of both:

• habituram esse
• redituram esse

It refers back to the subject of dicit, which is Mater.

So:

• Mater dicit se... = Mother says that she...

Because the she inside the reported statement is the same person as Mother, Latin uses the reflexive se.

Because the person being referred to is the same as the subject of the main verb.

• se refers back to the subject of the main clause
• eam would refer to some other female person

So:

• Mater dicit se redituram esse = Mother says that she herself will return
• Mater dicit eam redituram esse = Mother says that she (some other woman) will return

This is a very important distinction in Latin indirect statement.

Because they agree with se, which refers to Mater.

The future infinitive is formed with:

• the future active participle
• plus esse

So:

• habituram esse
• redituram esse

The participles habituram and redituram must agree with the subject of the infinitive:

• se = accusative singular
• refers to mater = feminine

Therefore the participles are:

• feminine
• singular
• accusative

If the subject were masculine, you would get -urum instead. If plural, the endings would change accordingly.

It is the future active infinitive of habeo.

Formation:

• future participle: habiturus, -a, -um
• plus esse

So:

• habituram esse = to be going to have / to be about to have

In indirect statement, this usually gives the sense of will have.

Likewise:

• redituram esse = future active infinitive of redeo
• meaning to be going to return / will return

Because this is an indirect statement, and Latin normally uses an infinitive there rather than a finite verb.

If Latin wanted a direct statement, it could say something like:

• Mater dicit: mox domum redibo. = Mother says: I will return home soon.

But once the statement is reported indirectly, Latin changes the structure:

• Mater dicit se mox domum redituram esse. = Mother says that she will return home soon.

So the future meaning is still there, but it is expressed by the future infinitive, not by a normal future indicative.

Esse is part of the future active infinitive:

• habituram esse
• redituram esse

Without esse, the form would just be the future participle, not the full infinitive.

That said, Latin sometimes omits a repeated esse, especially in context where the meaning is clear. But in a full, careful sentence like this, keeping esse is completely normal.

So here the structure is explicit and clear:

• se ... habituram esse
• sed mox domum redituram esse

Yes, redituram esse also has the same subject, but Latin often leaves out a repeated word when it is easily understood.

So the full sense is:

• Mater dicit se negotium breve in foro habituram esse, sed se mox domum redituram esse.

The second se is omitted because it would be repetitive. Latin regularly does this when the subject clearly stays the same.

Negotium breve is the object of habituram esse.

• negotium = accusative singular neuter
• breve = adjective agreeing with negotium

So:

• negotium breve = a short business matter / a short errand / a brief task

The adjective is breve because it agrees with negotium:

• neuter
• singular
• accusative

It does not describe mater. It describes negotium.

Because brevis is the dictionary form, but adjectives have to agree with the nouns they modify.

Here:

• negotium is neuter singular accusative
• so brevis, breve becomes breve

Agreement is in:

• gender
• number
• case

So:

• nominative masculine/feminine singular: brevis
• nominative/accusative neuter singular: breve

Since negotium is neuter singular accusative, breve is the correct form.

In foro means in the forum or in the marketplace/public square.

The preposition in can take different cases:

• in + ablative = in/on a place, indicating location
• in + accusative = into/onto, indicating motion toward

Here the meaning is location:

• she will have this business in the forum

So Latin uses:

• in foro = in the forum

with foro in the ablative singular.

Because Latin often uses the accusative without a preposition to express motion toward home.

So:

• domum = homeward / to home / home

This is a special idiomatic use, and it is very common.

Compare:

• domi = at home
• domo = from home
• domum = to home / homeward

So mox domum redituram esse means that she will return home soon.

Mox is an adverb meaning soon.

It modifies redituram esse:

• mox domum redituram esse = that she will return home soon

Its placement is flexible. Latin word order is freer than English word order, so mox can be placed where it sounds natural or where the writer wants emphasis.

Because Latin relies much more on inflected endings than on word order.

For example, you can tell the jobs of the words from their forms:

• Mater = nominative subject of dicit
• se = accusative subject of the infinitives
• negotium breve = object of habituram esse
• in foro = location
• domum = motion toward home

That means Latin can arrange words for emphasis, rhythm, or clarity more freely than English can.

In this sentence, the order is quite natural:

• main clause first: Mater dicit
• then the first reported idea
• then sed
• then the second reported idea

In some contexts, Latin can use fore as an alternative future infinitive, especially with forms of sum or in certain stylistic situations. But for ordinary verbs like habeo and redeo, the normal and straightforward way is exactly what you see here:

• habituram esse
• redituram esse

So for a learner, this sentence shows the standard pattern you should recognize first.

Yes, effectively it is.

Literally, habere negotium is to have business, but in natural English that often means something like:

• to have some business to take care of
• to have an errand
• to have a task or matter to attend to

So negotium breve in foro habituram esse means she says she will have a short bit of business in the forum/marketplace.

A learner may be tempted to translate very literally, but the phrase works more naturally as a short errand or a brief matter of business.