Ispod skrivenog magneta pronašli smo polugu i zrcalno pismo.

Ispod means under, below, or beneath.

In Croatian, ispod normally takes the genitive case, so magnet becomes magneta.

• magnet = magnet
• magneta = of/from/under the magnet, depending on the preposition and context

So:

• ispod magneta = under the magnet

Because skrivenog describes magneta, it also has to be in the genitive.

Because both words have to match the grammar required by ispod.

The basic form is:

• skriveni magnet = hidden magnet

But after ispod, the noun goes into the genitive singular, and the adjective changes with it:

• skrivenog magneta = of the hidden magnet / under the hidden magnet

So this is just normal adjective-noun agreement:

• gender: masculine
• number: singular
• case: genitive

Historically, it is a participle, but in this sentence it works like an adjective.

Skriven comes from the verb sakriti / skrivati, meaning to hide. In actual use, though, learners can safely treat skriven as an adjective meaning hidden.

So:

• skriveni predmet = a hidden object
• skrivenog magneta = of the hidden magnet

You do not need to analyze it differently from a normal adjective when you decline it.

It is the perfect tense, which is the normal way to talk about a completed past action in Croatian.

It is built from:

• the l-participle: pronašli
• the present tense of biti: smo = we are

Together:

• pronašli smo = we found

So literally, it is something like we have found, but in normal English translation it is usually just we found.

Because Croatian usually drops subject pronouns when they are already clear from the verb.

In pronašli smo, the smo already tells you the subject is we.

So:

• pronašli smo = we found
• mi smo pronašli also means we found, but mi is usually added only for emphasis or contrast

For example:

• Mi smo pronašli polugu, a oni kartu. = We found the lever, and they found the map.

Because the l-participle agrees with the subject in number and also, in the plural, often in gender.

Here, pronašli is plural masculine. In Croatian, that form is used for:

• a group of men
• a mixed-gender group
• sometimes a group when masculine is the default grammatical form

If the speakers were all female, it would be:

• pronašle smo = we found

So this sentence suggests that the group speaking is either masculine or mixed.

Because pronaći is a perfective verb, used for a completed result: the finding happened and was achieved.

• pronaći / pronašli smo = we found, we discovered
• nalaziti / nalazili smo = we were finding / used to find

In this sentence, the action is a single completed event, so pronašli smo is the natural choice.

Also, compared with našli smo, pronašli smo can sound a little more like discovered or managed to find, though both can often be translated simply as found.

Because polugu is the accusative singular form, and it is the direct object of pronašli smo.

The basic form is:

• poluga = lever

But feminine nouns ending in -a usually change to -u in the accusative singular:

• Vidim polugu. = I see the lever.
• Pronašli smo polugu. = We found a/the lever.

So:

• nominative: poluga
• accusative: polugu

Because pismo is a neuter noun, and for many neuter nouns the nominative and accusative singular are the same.

So:

• nominative: pismo
• accusative: pismo

That is why you get:

• pronašli smo pismo = we found a/the letter / writing

By contrast, poluga is feminine, so its accusative singular changes to polugu.

Because zrcalno agrees with pismo.

• pismo is neuter singular
• therefore the adjective must also be neuter singular

So:

• zrcalno pismo = mirror writing / mirrored writing

The -o ending is the normal neuter singular adjective ending here.

Also, since pismo is a direct object and its accusative form is the same as the nominative, the whole phrase stays:

• zrcalno pismo

Because Croatian word order is quite flexible, and putting that phrase first helps set the scene.

So the sentence starts with the location:

• Ispod skrivenog magneta = under the hidden magnet

Then comes the action:

• pronašli smo = we found

This is very natural in narration, where the speaker first tells you where something happened.

Yes, that is also possible.

Croatian clitics such as smo often like to appear near the second position in the clause, so many learners expect:

• Ispod skrivenog magneta smo pronašli polugu i zrcalno pismo.

That version is very normal.

The given version:

• Ispod skrivenog magneta pronašli smo polugu i zrcalno pismo.

is also possible, especially in a narrative style where pronašli smo is kept together as a verbal unit. The difference is more about rhythm and style than basic meaning.

Sometimes both can be translated as under, but they are not used the same way.

• ispod takes the genitive
• pod usually takes the instrumental for location, and the accusative for motion

Examples:

• ispod magneta = below / beneath the magnet
• pod magnetom = under the magnet

In many contexts they overlap, but ispod often emphasizes position below something, while pod can feel more like being under it in a more direct spatial sense. In this sentence, ispod works very naturally.

Because Croatian does not have articles like English.

So forms such as:

• magnet
• poluga
• pismo

can mean a magnet / the magnet, a lever / the lever, a writing / the writing, depending on context.

English has to choose a or the, but Croatian usually leaves that to the situation or to other clues in the sentence.