Mater dicit laborem in agro nimis gravem esse.

Because after verbs like dicit when Latin reports a statement indirectly, it often uses the accusative + infinitive construction.

So instead of saying something like Mother says that the work is very heavy, Latin says, more literally:

Mother says the work to be very heavy.

In that pattern:

• laborem = the subject of the indirect statement, so it goes into the accusative
• esse = the infinitive verb, to be

That is why it is laborem, not labor.

This is the classic accusative-and-infinitive construction, often abbreviated as ACI.

The parts are:

• laborem = accusative subject of the indirect statement
• gravem = predicate adjective describing laborem
• esse = infinitive verb

So laborem ... gravem esse means that the work is heavy.

With nimis included, it becomes:

that the work is too heavy / excessively heavy

And with in agro:

that the work in the field is too heavy

Because gravem agrees with laborem.

In the ACI construction, the adjective describing the accusative subject also goes into the accusative. Since laborem is masculine singular accusative, the adjective must match it:

• nominative: gravis
• accusative: gravem

So:

• labor gravis est = the work is heavy
• mater dicit laborem gravem esse = mother says that the work is heavy

Because the indirect statement needs a verb, and here the verb is to be.

If the direct statement were:

Labor in agro nimis gravis est.
The work in the field is too heavy.

then after dicit, Latin changes est into the infinitive esse:

Mater dicit laborem in agro nimis gravem esse.

That is the normal way Latin turns a direct statement into indirect statement after verbs of saying, thinking, knowing, hearing, and similar verbs.

Latin word order is much freer than English word order. Infinitives, especially esse, often come at or near the end of the clause.

So laborem in agro nimis gravem esse is a very natural Latin order.

That said, Latin could rearrange the words for emphasis. For example, the sentence would still be understandable in other orders, but the given order is standard and elegant.

In agro means in the field or on the farm land.

• in with the ablative often means in, on, or within
• agro is the ablative singular of ager, meaning field or land

So in agro tells you where the labor is happening.

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

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

Here the meaning is location:

the work in the field

So Latin uses in agro.

If it meant movement into the field, it would be in agrum.

Nimis means too much, excessively, or too.

So gravis means heavy or burdensome, but nimis gravis means:

• too heavy
• overly burdensome
• excessively hard

It strengthens the adjective in a negative or excessive sense.

It can mean both, depending on context.

Labor often means:

• work
• toil
• effort
• hardship

In laborem in agro, it strongly suggests farm work or labor in the field, so it sounds like physical agricultural work here.

Because Latin usually does not use that in this kind of sentence. English says:

Mother says that the work is too heavy.

But Latin normally uses the ACI instead of a that-clause:

Mater dicit laborem ... esse.

So English uses a subordinate clause with that, while Latin often uses an accusative subject plus infinitive.

Dicit is present tense, third person singular.

It means:

• she says
• mother says

It comes from dico, dicere, meaning to say or to speak.

Because the subject is mater, singular, the verb is also singular.

Because mater is a third-declension noun, not a first-declension noun.

Its basic forms are:

• nominative singular: mater
• accusative singular: matrem

So mater is the subject of dicit, and subjects go in the nominative.

A learner might expect a mother-word to look like a first-declension noun, but mater, like pater and frater, belongs to the third declension.

In some contexts, Latin can omit forms of esse, especially in poetry or very compressed style. But in a standard prose sentence like this, esse is normally expressed in the ACI.

So here esse is exactly what you would expect.

The direct statement would be:

Labor in agro nimis gravis est.
The work in the field is too heavy.

Then after mater dicit, Latin changes it like this:

• labor → laborem
• gravis → gravem
• est → esse

So the indirect version is:

Mater dicit laborem in agro nimis gravem esse.

It is important for style and emphasis, but not as rigidly as in English.

Latin shows grammatical relationships mainly through endings, not position. So you can identify:

• mater as the subject of dicit
• laborem as the accusative subject of the indirect statement
• gravem as agreeing with laborem
• esse as the infinitive
• in agro as a prepositional phrase
• nimis as modifying gravem

The order given is natural and easy to follow, but Latin does not depend on word order as heavily as English does.

Because of agreement and sense.

Gravem is masculine singular accusative, and laborem is also masculine singular accusative, so they match grammatically.

Also, semantically it makes sense: the sentence is saying that the work is too burdensome, not that the field is burdensome.

So both grammar and meaning point to gravem describing laborem.