Miles scutum grave gerit, sed serva tantum saccum levem portat.

Miles is singular, not plural. It means soldier.

In Latin, -es can be a singular ending in some third-declension nouns. The plural of miles is milites.

So in this sentence:

• miles = the soldier / a soldier
• serva = the slave woman / a slave woman

Both subjects are singular.

They are in the nominative case, which is the case normally used for the subject of a clause.

Each half of the sentence has its own subject and verb:

• Miles ... gerit = the soldier ... carries/wears
• sed serva ... portat = but the slave woman ... carries

So the sentence is made of two coordinated clauses joined by sed.

They are in the accusative singular because they are the direct objects of the verbs.

• gerit takes an object: the soldier carries/wears a shield
• portat takes an object: the slave woman carries a bag

So:

• scutum = accusative singular of scutum
• saccum = accusative singular of saccus

In Latin, the object is shown by case endings rather than mainly by word order.

Because adjectives in Latin must agree with the nouns they describe in gender, number, and case.

Here:

• scutum is neuter accusative singular
• so its adjective is grave, also neuter accusative singular

But:

• saccum is masculine accusative singular
• so its adjective is levem, also masculine accusative singular

So the different endings show agreement with different kinds of nouns.

Because scutum is neuter.

The adjective gravis, grave has:

• gravem for masculine/feminine accusative singular
• grave for neuter nominative/accusative singular

Since scutum is a neuter noun, the correct form is grave.

This is a very common pattern in Latin: neuter accusative singular adjectives often look different from masculine or feminine ones.

Here tantum means only and is being used adverbially.

So the sense is:

• the soldier carries a heavy shield,
• but the slave woman carries only a light bag

It is not agreeing with serva or saccum as an adjective here. Instead, it limits the idea of the second clause, especially the object phrase saccum levem.

A natural English translation is but the slave woman carries only a light bag.

In practice, it emphasizes that the slave woman carries only this relatively small/light thing, not something heavier like the soldier does.

Because Latin word order is flexible, adverbs like tantum can sit near the word or phrase they emphasize. In this sentence, the most natural understanding is:

• serva tantum saccum levem portat = the slave woman carries only a light bag

So the emphasis is not really only the slave woman, but rather only a light bag.

Yes, both can be translated as carries, but there is a slight difference in feel.

• gerit often suggests wearing, bearing, or carrying as equipment
• portat often means more straightforwardly carries or transports

So miles scutum grave gerit sounds very natural for a soldier who is bearing/wearing a shield as part of his gear.

And serva ... saccum levem portat sounds natural for someone simply carrying a bag.

In beginner texts, both are often translated simply as carries, but the choice of verb is still meaningful.

Because Classical Latin does not have articles like English the and a/an.

So:

• miles can mean the soldier or a soldier
• scutum can mean the shield or a shield

You decide from context which English article sounds best.

That is why a single Latin sentence can often be translated into English in more than one natural way.

Latin word order is much more flexible than English word order because case endings show the grammatical roles.

This sentence uses a very clear, beginner-friendly order:

• subject
• object + adjective
• verb

So:

• Miles scutum grave gerit
• serva tantum saccum levem portat

But Latin could rearrange many of these words without changing the basic meaning, as long as the endings remain clear. Different orders would mainly change emphasis, not grammar.

They often do, especially in simple textbook sentences, but they do not have to.

In this sentence:

• scutum grave
• saccum levem

the adjectives come after the nouns. That is perfectly normal.

But Latin can also put adjectives before nouns, or even separate them from their nouns, because agreement in gender, number, and case keeps the relationship clear.

So grave clearly goes with scutum, and levem clearly goes with saccum, even if the order were changed.

They tell you that each verb is third person singular present active indicative.

So:

• gerit = he/she carries, wears, bears
• portat = he/she carries

The -t ending is the key sign of third person singular in the present tense.

That matches the singular subjects:

• miles ... gerit
• serva ... portat

So even if the subject were omitted, the verb form would still tell you that the subject is he/she/it, singular.