Piscator tridente thynnum capit.

Because piscator is in the nominative singular, the form Latin normally uses for the subject of the sentence.

The noun is:

• piscator = fisherman

Its ending here shows it is the one doing the action. So piscator is the fisherman as the subject.

Because thynnum is in the accusative singular, which is the case commonly used for the direct object.

So in this sentence:

• piscator = the fisherman = subject
• thynnum = the tuna = direct object

That tells you the fisherman is catching the tuna, not the other way around.

This is a very common Latin pattern. Tridente is in the ablative singular, and here the ablative is being used as an ablative of means or instrument.

That means Latin can express:

• tridente = with a trident / by means of a trident

So Latin often does not need a separate preposition where English does.

Tridente is ablative singular.

It comes from the noun:

• tridens, tridentis = trident

A third-declension noun like this often has:

• nominative singular: tridens
• accusative singular: tridentem
• ablative singular: tridente

So the ending -e is a clue that it is ablative singular.

Capit is:

• third person singular
• present tense
• active voice
• indicative mood

It comes from the verb:

• capio, capere, cepi, captum = catch, take, seize

So capit means:

• he/she/it catches
• or sometimes is catching, depending on context

Here it agrees with the singular subject piscator.

Because the subject piscator is singular.

Latin verbs change their endings to match the subject:

• capit = he/she/it catches

If the subject were plural, the verb would also be plural. For example:

• Piscatores tridente thynnum capiunt = The fishermen catch a tuna with a trident

So capit must be singular because piscator is singular.

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

So:

• piscator can mean the fisherman or a fisherman
• tridente can mean with a trident
• thynnum can mean the tuna or a tuna

You decide from context which English article sounds best.

Latin word order is more flexible than English word order because the endings show what each word is doing.

So Piscator tridente thynnum capit means the same basic thing as:

• Piscator thynnum tridente capit
• Thynnum piscator tridente capit
• Tridente piscator thynnum capit

The endings still show:

• piscator = subject
• thynnum = object
• tridente = means/instrument

That said, word order in Latin can still affect emphasis or style.

Thynnum is a Greek-derived word. It refers to a kind of tuna or tunny.

Its dictionary form is typically:

• thynnus = tuna

Then the accusative singular is:

• thynnum

Because it is a borrowed word, the spelling may look less familiar than more basic Latin vocabulary. You may also sometimes see related spellings in different texts.

Yes, the ablative case has several uses, so in other contexts an ablative form could mean different things. But in this sentence, tridente is most naturally understood as an ablative of means.

Why?

• It is a thing, not a person.
• It fits naturally as the tool used for catching the fish.
• No preposition is needed with this use.

So here tridente is best understood as with a trident.

The dictionary forms are:

• piscator, piscatoris = fisherman
• tridens, tridentis = trident
• thynnus = tuna
• capio, capere, cepi, captum = catch, take, seize

When learning Latin, it is important to get used to recognizing the form you see in the sentence and connecting it back to its dictionary form.

A useful step-by-step method is:

1. Find the verb: capit = catches
2. Find the subject in the nominative: piscator = the fisherman
3. Find the direct object in the accusative: thynnum = the tuna
4. Notice any ablative of means: tridente = with a trident

So the structure is:

• piscator = subject
• tridente = instrument
• thynnum = object
• capit = verb

That kind of analysis is very helpful when reading Latin.