Navicularii interest utrum naulum hodie persolvatur.

It has two pieces:

• navicularii interest = an impersonal main clause, literally something like it matters to the shipowner
• utrum naulum hodie persolvatur = an indirect yes/no question, whether the freight is paid today

So the whole utrum-clause is the thing that matters.

Interest is being used impersonally here. Latin often says it matters rather than someone is interested.

So navicularii is not the subject. The real content is the clause utrum naulum hodie persolvatur. In effect:

• Whether the freight is paid today = what matters
• navicularii = the person whose concern it is

Here navicularii is genitive singular.

That form can look ambiguous in isolation, because -ii could also be nominative plural in some nouns. But the syntax makes the meaning clear: with interest, the person concerned is normally put in the genitive, so navicularii interest means it matters to the shipowner.

If it were nominative plural, it would not fit this construction naturally.

That is the regular idiom with impersonal interest meaning it matters / it is of concern. Latin expresses the person concerned differently from English.

English says:

• It matters to the shipowner
• The shipowner cares whether...

Latin says:

• navicularii interest

So the genitive marks the person whose interest or concern is involved.

A useful extra note: with some pronouns, Latin often uses forms like mea interest, tua interest, nostra interest, rather than an ordinary genitive pronoun.

Utrum introduces an indirect yes/no question. In English, that is usually whether.

So utrum naulum hodie persolvatur means whether the freight is paid today.

Even though no second alternative is stated, the contrast is understood:

• whether it is paid today or not

Because Latin uses the subjunctive in indirect questions.

Once the sentence says utrum = whether, the verb inside that question normally goes into the subjunctive. So:

• direct question: persolvitur? = is it being paid?
• indirect question: utrum persolvatur = whether it is being paid

That is why persolvatur appears, not persolvitur.

It is:

• third person singular
• present subjunctive
• passive
• from persolvo

So grammatically it means may be paid / is being paid in form, but in this construction the natural English translation is usually just is paid or gets paid. Depending on context, English might even use will be paid, but the Latin form itself is present subjunctive.

It is the subject of the passive verb.

In the active, you would have something like:

• aliquis naulum persolvit = someone pays the freight

There naulum is the object.

But in the passive:

• naulum persolvatur = the freight is paid

Now naulum is the grammatical subject.

This can be confusing because naulum is a neuter singular noun, and in Latin the nominative and accusative neuter singular have the same form. So it looks the same in both roles.

Persolvo often has the sense of pay fully, settle, or discharge completely. The prefix per- can add a sense of completion.

So naulum persolvatur is not just the freight is paid in a vague sense, but more specifically the freight charge is settled/paid off.

Hodie modifies persolvatur. It tells you when the paying happens:

• whether the freight is paid today

Its position between naulum and persolvatur is normal Latin word order flexibility. Latin does not need to place adverbs exactly where English would. The meaning stays clear from the forms and the overall structure.

Because Latin does not always state both sides of the alternative explicitly.

Utrum by itself can already mean whether. The unstated alternative is obvious:

• whether the freight is paid today or not

If the writer wanted to spell out both options, Latin could use something like utrum ... an ..., but it is not necessary here.