Tessellarius crustam sculpit; pavimentarius eam pumice polit.

They are both nouns for workers, formed with the common ending -arius.

• tessellarius = a worker in tessellae (small cubes or tiles), so a mosaic worker
• pavimentarius = a worker in pavimentum (a floor or pavement), so a floor-layer or pavement worker

A learner may notice that Latin often uses this -arius ending to make occupation words.

Because crustam is the direct object of sculpit. It is the thing being carved.

The base noun is crusta, a first-declension noun. Its forms include:

• nominative singular: crusta
• accusative singular: crustam

Since sculpit means carves, Latin puts the thing carved into the accusative case, so we get crustam.

eam means her / it in the feminine accusative singular, and here it refers back to crustam.

So:

• crustam = feminine singular accusative
• eam = feminine singular accusative

The pronoun matches the noun it refers to in gender and number, and here it also has the right case because it is again the direct object, this time of polit.

Because Latin often avoids repeating a noun when a pronoun will do.

So instead of saying:

• pavimentarius crustam pumice polit

it says:

• pavimentarius eam pumice polit

Both are possible, but eam is smoother and more natural because the referent is already clear from the first clause.

Because this is an ablative of means or instrument.

Latin often uses the ablative case by itself to mean:

• with
• by means of
• using

So pumice means with pumice or using pumice.

There is no need for a separate word like with here.

It is ablative singular.

The dictionary form is pumex. This is a third-declension noun. One of its forms is:

• nominative singular: pumex
• ablative singular: pumice

So in this sentence, pumice is the instrument used for polishing.

Both are third-person singular present active indicative.

That means:

• sculpit = he/she carves
• polit = he/she polishes

Here the subjects are the two workers:

• tessellarius sculpit = the mosaic worker carves
• pavimentarius polit = the floor-worker polishes

So both verbs are in the same tense and are describing actions in the present.

Because Latin word order is much more flexible than English word order, and it very often places the verb near or at the end of the clause.

So this pattern is very normal:

• subject + object + verb
• subject + object + instrument + verb

Latin endings show the grammatical roles, so the language does not depend on a fixed word order as much as English does.

Yes, often they could.

For example, eam pavimentarius pumice polit would still mean the same basic thing, because the endings tell you what each word is doing.

However, the given order is natural and clear:

• the worker comes first
• then the object
• then the instrument
• then the verb

Different word orders can change emphasis, even when the core meaning stays the same.

Because Latin has no articles.

English says things like:

• the mosaic worker
• a floor-worker

Latin usually just says:

• tessellarius
• pavimentarius

Whether you translate that as the or a depends on the context.

Yes, very helpfully so.

• sculpit comes from sculpere, which is related to English sculpt, sculpture
• polit comes from polire, related to English polish and polite in the older sense of smoothed/refined
• pumice is obviously related to English pumice
• pavimentarius is related to English pavement
• tessellarius is related to English tessellated

These connections can make the vocabulary much easier to remember.

Not really. It is mainly a modern punctuation choice.

The semicolon shows that the two clauses are closely connected:

• first worker does one action
• second worker does the next action to the same thing

Ancient Latin texts were not punctuated in exactly the same way modern printed texts are, so the semicolon helps the reader, but it is not itself a grammatical feature of the sentence.