Tempestas nautas e portu exire vetuit.

The sentence has this structure:

• Tempestas = the subject
• nautas = the direct object
• exire = an infinitive that tells what action was prevented
• vetuit = the main verb

So the pattern is:

subject + person prevented + action prevented + verb

Latin often uses vetare + accusative + infinitive, meaning to forbid/prevent someone to do something or more natural English to prevent someone from doing something.

Because nautas is the direct object of vetuit.

The verb veto, vetare, vetui, vetitum means forbid, prevent, or keep from. With this verb, the person being forbidden is put in the accusative.

So:

• nauta = sailor
• nautas = sailors (accusative plural)

In this sentence, the storm is preventing the sailors, so nautas must be accusative.

Because after vetuit, Latin commonly uses an infinitive to express the action that was stopped or forbidden.

So:

• nautas = the sailors
• exire = to go out / to leave

Together, nautas exire vetuit means literally something like:

it prevented the sailors to leave

But in natural English we usually say:

it prevented the sailors from leaving

This is a normal Latin construction with veto.

Vetuit is:

• 3rd person singular
• perfect active indicative
• from veto, vetare

It means forbade, prevented, or kept ... from.

Why 3rd person singular? Because the subject is tempestas, which is singular.

So tempestas ... vetuit = the storm prevented.

Because the preposition e or ex means out of or from, and it takes the ablative case.

So:

• portus = harbor, port
• portu = ablative singular

Therefore:

• e portu = out of the harbor / from the harbor

This is a very common Latin pattern: a preposition of separation or motion away often uses the ablative.

Both e and ex mean the same thing here: out of, from.

Latin often uses:

• ex before vowels or sometimes for clarity/emphasis
• e before consonants

Since portu begins with p, e portu is perfectly normal.

So there is no important difference in meaning between e portu and ex portu here.

Exire is the infinitive of exeo, exire, meaning to go out, to go forth, or to leave.

In this sentence, because of e portu, it clearly means:

to go out from the harbor
or more naturally,
to leave the harbor

So exire by itself means to go out, but the phrase e portu exire makes the direction explicit.

Yes, exire already contains the idea of going out, but Latin often adds a prepositional phrase to show more precisely out of what place.

So:

• exire = to go out
• e portu exire = to go out from the harbor

This is not redundant in a bad way. It is just clearer and more specific.

English can do the same thing:

• to go out
• to go out of the harbor

Latin word order is much more flexible than English word order because Latin shows grammatical relationships mainly through endings, not position.

English depends heavily on word order:

• The storm prevented the sailors from leaving the harbor

Latin can move things around more freely:

• Tempestas nautas e portu exire vetuit
• Nautas tempestas e portu exire vetuit
• E portu nautas exire tempestas vetuit

These can all mean basically the same thing, though different orders may give slightly different emphasis.

In your sentence, the verb vetuit comes at the end, which is very common in Latin.

Yes. Tempestas is the subject because it is in the nominative singular form and it matches the singular verb vetuit.

So even if word order changes, the ending helps you identify its role:

• tempestas = nominative singular, so it can be the subject
• nautas = accusative plural, so it is the object

That is why Latin readers look at case endings first, not just position.

You would look them up like this:

• tempestas, tempestatis = storm
• nauta, nautae = sailor
• portus, portus = harbor, port
• exeo, exire, exii/exivi, exitum = go out, leave
• veto, vetare, vetui, vetitum = forbid, prevent

This is useful because the sentence contains inflected forms, not always the exact dictionary form.

Because portus belongs to the fourth declension, not the second.

That can confuse beginners because the nominative singular ends in -us, which often suggests second declension. But portus is fourth declension.

Its ablative singular is:

• portu

not porto

So e portu is correct.

Yes. Latin sometimes expresses prohibition or prevention in other ways, but with veto, the accusative + infinitive construction is very standard.

So this sentence is a very normal and straightforward way to say that the storm prevented the sailors from leaving the harbor.

A learner should especially remember this pattern:

veto + accusative + infinitive

For example:

• magister pueros currere vetuit = the teacher forbade the boys to run
• tempestas nautas exire vetuit = the storm prevented the sailors from leaving