Pavimentarius pavimentum aequat.

Because pavimentarius is in the nominative singular, the case normally used for the subject of a sentence.

A beginner-friendly way to see it:

• -us is a very common nominative singular ending for a 2nd-declension masculine noun.
• So pavimentarius means the floor-layer / paver as the doer of the action.

In contrast, pavimentum is not marked as a masculine nominative subject here; it is functioning as the direct object.

Pavimentum is in the accusative singular, which is the case commonly used for a direct object.

Here the verb aequat is something the subject does to something. The thing being leveled is the direct object, so Latin puts it in the accusative:

• pavimentarius = the one doing the action
• pavimentum = the thing receiving the action

A useful extra point: because pavimentum is a neuter 2nd-declension noun, its nominative singular and accusative singular look the same: pavimentum. So you identify its role from the rest of the sentence, not from that form alone.

That is a very good question, because neuter nominative singular and neuter accusative singular are often identical.

What settles it here is pavimentarius:

• pavimentarius is clearly nominative singular
• so it naturally serves as the subject
• therefore pavimentum is understood as the object

If Latin wanted pavimentarius to be the object instead, you would expect pavimentarium, not pavimentarius.

So the endings together tell you the structure.

Aequat is:

• 3rd person
• singular
• present tense
• active voice
• indicative mood

So it means he/she/it levels, makes level, or equalizes, depending on context.

In this sentence, the subject is singular, so the verb is singular too.

The ending -t is especially important: in Latin present tense, -t is the normal 3rd-person singular ending.

Latin often leaves out words that English requires.

1. No separate he

Latin does not need a separate subject pronoun here because the verb ending already tells you the person and number:

• aequat = he/she/it levels

So a pronoun like is would usually be unnecessary unless you wanted emphasis.

2. No word for the or a

Classical Latin has no articles like English the or a/an.

So:

• pavimentarius can mean the paver or a paver
• pavimentum can mean the pavement or a pavement

You decide from context which English wording is best.

Yes. Latin word order is much freer than English word order because the endings do a lot of the grammatical work.

So all of these could express the same basic idea:

• Pavimentarius pavimentum aequat.
• Pavimentum pavimentarius aequat.
• Aequat pavimentarius pavimentum.

The core meaning stays the same because the endings still show who is doing what.

However, changing the order can change emphasis or style. The version you were given is a very straightforward, beginner-friendly order:

• subject
• object
• verb

In this sentence, pavimentarius is being used as a noun: a worker connected with pavements/floors, that is, a paver or floor-layer.

But its form is built in a way that is very common for Latin words connected with occupations or associations. The ending -arius often means something like:

• connected with
• concerned with
• belonging to

So pavimentarius is a word formed from pavimentum and means a person associated with pavements or flooring.

That is one reason it may look adjective-like, even though here it functions as a noun.

A learner would normally meet them in roughly these forms:

• pavimentarius, pavimentarii (masculine noun)
• pavimentum, pavimenti (neuter noun)
• aequo, aequare, aequavi, aequatum (verb)

Why this matters:

• For nouns, the dictionary usually gives the nominative singular and genitive singular, which help you identify the declension.
• For verbs, Latin dictionaries typically give the principal parts, which help you build the different tenses and forms.

So from those dictionary forms you can tell:

• pavimentarius = 2nd declension masculine
• pavimentum = 2nd declension neuter
• aequo = 1st conjugation verb

Because it comes from the 1st-conjugation verb aequare.

In the present tense, 1st-conjugation verbs commonly go like this:

• aequo = I level
• aequas = you level
• aequat = he/she/it levels

So the -at ending tells you this is the 3rd-person singular present active form.

This is the same pattern you see in very common verbs like:

• amo, amas, amat
• laudo, laudas, laudat

Because in Latin the verb normally agrees with the subject, not with the direct object.

Here:

• subject = pavimentarius = singular
• verb = aequat = singular

The object pavimentum does not control the verb ending.

So the agreement is:

• pavimentarius ... aequat = singular subject with singular verb

That is the same basic principle as in English, even though Latin shows it more clearly in verb endings.

In a commonly taught Classical pronunciation, a rough guide is:

• pavimentarius = pa-wi-men-TA-ri-us
• pavimentum = pa-wi-MEN-tum
• aequat = AE-kwat

A few helpful notes:

• v is pronounced like English w
• ae is usually like ai in aisle or eye
• qu is like kw
• the stress in pavimentarius falls on ta
• the stress in pavimentum falls on men

So the whole sentence sounds roughly like:

pa-wi-men-TA-ri-us pa-wi-MEN-tum AE-kwat