He löysivät kultaa.

• he = they
• löysivät = found
• kultaa = gold / some gold

So the sentence means They found gold.

Because he means they, and in standard Finnish the verb agrees with the subject.

The verb here is in the 3rd person plural:

• hän löysi = he/she found
• he löysivät = they found

So he löysivät is the normal written-language combination.

The dictionary form is löytää, meaning to find.

This verb changes quite a bit when conjugated:

• löytää = to find
• löysi = found (he/she found)
• löysivät = found (they found)

So löysivät is the past tense plural form of löytää.

Because kultaa is the partitive form of kulta.

• kulta = gold
• kultaa = gold / some gold / an unspecified amount of gold

In this sentence, kultaa suggests they found some gold, not a specific, fully defined piece or amount. This is very common in Finnish with materials and uncountable things.

This is about the difference between a partitive object and a total object.

• He löysivät kultaa = They found gold / some gold
• He löysivät kullan = more like They found the gold or they found the whole/specific gold

With kultaa, the amount is indefinite or non-specific.
With kullan, the object sounds more definite or complete.

For a sentence like They found gold, kultaa is the natural choice.

Finnish does not have articles like English a/an and the.

So Finnish usually expresses those ideas through:

• context
• word order
• case endings

That is why kultaa can mean simply gold or some gold, depending on context.

Sometimes, yes, especially if the subject is already clear from context.

However, with 3rd person forms, Finnish usually keeps the subject more often than with 1st and 2nd person.

So:

• He löysivät kultaa = clear on its own
• Löysivät kultaa = possible in context, but less self-contained

In a standalone sentence, keeping he is safer for learners.

In standard written Finnish, yes: He löysivät kultaa.

In colloquial spoken Finnish, people often say something more like:

• Ne löysi kultaa
• or even shorter spoken forms depending on the dialect

A very important difference:

• written standard: he löysivät
• everyday speech: often ne löysi

So your sentence is good standard Finnish.

The basic word order is:

He löysivät kultaa.
subject + verb + object

That is the most neutral order.

But Finnish word order is flexible, and changing it can change emphasis:

• Kultaa he löysivät. = Gold is what they found
• He kultaa löysivät. = possible, but more marked or literary

For a beginner, He löysivät kultaa is the best neutral pattern.

A rough guide is:

LÖY-si-vät

Useful sound notes:

• ö is like the vowel in French peur or German schön
• y is a front rounded vowel, like German ü
• ä is somewhat like the a in cat, but not exactly

Also, Finnish stress is normally on the first syllable:

LÖY-si-vät

It is singular in form, even though in English we do not usually count gold.

Here kultaa is the partitive singular of kulta.

That fits because gold is being treated as a substance or material, not as countable separate items.

So:

• kulta = gold
• kultaa = some gold / gold (as a substance)

Yes. löysivät is the past tense.

So it refers to something that happened and was completed in the past:

• He löytävät kultaa = They find / are finding gold
• He löysivät kultaa = They found gold

The past tense ending here is part of the verb form löysivät.