Na stolu su dva podmetača, ali opet nema mjesta za veliki lonac.

Because na can take different cases depending on meaning:

• na + accusative = motion onto something
  
  • Stavljam lonac na stol. = I am putting the pot onto the table.
• na + locative = location on something
  
  • Lonac je na stolu. = The pot is on the table.

In your sentence, the coasters are already located on the table, so Croatian uses the locative: na stolu.

Su is the 3rd person plural form of biti (to be), and in Croatian it is an unstressed clitic. Clitics usually go in the second position in the clause.

So:

• Na stolu = first phrase
• su = clitic in second position
• dva podmetača = the rest

That is why Na stolu su dva podmetača sounds natural.

English speakers often expect something closer to Dva podmetača su na stolu, which is also possible, but Croatian word order is more flexible and clitic placement has its own rules.

After the numbers dva, tri, and četiri, Croatian usually does not use the normal nominative plural form of the noun.

So:

• jedan podmetač
• dva podmetača
• tri podmetača
• četiri podmetača
• pet podmetača

For masculine nouns like podmetač, the form after dva/tri/četiri looks like the genitive singular.

So podmetači is the regular nominative plural, but after dva you say dva podmetača.

In meaning, it is plural: it means two coasters/trivets/mats.

But grammatically, after dva, the noun takes a special counted form that often looks like the genitive singular. So it can feel strange to English speakers: the meaning is plural, but the form is not the normal plural form.

This is very common in Croatian number phrases.

Because after nema (there is not / there isn’t / there isn’t any), Croatian often uses the genitive.

Here:

• mjesto = place / spot / room / space
• mjesta = genitive singular

So nema mjesta literally means something like there is no space.

This is a very common pattern:

• Ima vremena. = There is time.
• Nema vremena. = There is no time.
• Ima vode. = There is water.
• Nema vode. = There is no water.

In this sentence, mjesta means room/space, not places.

Opet most often means again, but in context it can also feel like:

• again
• still
• yet again
• once again

In this sentence, it suggests a repeated problem:

• there are two coasters on the table,
• but again / still / yet again there is no room for the big pot.

So opet adds a sense of frustration or repetition.

Because the preposition za here means for, and in this meaning it takes the accusative.

So:

• lonac = nominative
• veliki lonac = accusative as well, for an inanimate masculine noun, it looks the same as nominative

That is why you get:

• za lonac
• za veliki lonac

The adjective veliki must agree with lonac in:

• gender: masculine
• number: singular
• case: accusative

Because nema mjesta is an impersonal expression. Croatian often says things like:

• Nema vremena. = There is no time.
• Nema problema. = There is no problem.
• Nema mjesta. = There is no room.

English uses there is/there are, but Croatian often just uses ima / nema without a separate dummy subject like there.

So the clause is complete even though it does not have an explicit subject the way English does.

Croatian has no articles, so there is no direct equivalent of a or the.

Whether something is definite or indefinite is usually understood from:

• context
• word order
• shared knowledge
• sometimes extra words like jedan, taj, ovaj, etc.

So na stolu can mean either:

• on the table
• on a table

In most natural translations here, English would say on the table, because the situation sounds specific.

Yes, Croatian word order is fairly flexible, but different orders change the focus or emphasis.

The original sentence:

• Na stolu su dva podmetača, ali opet nema mjesta za veliki lonac.

This is natural and neutral.

You could also say:

• Dva podmetača su na stolu, ali opet nema mjesta za veliki lonac.

This puts more focus on two coasters.

However, you cannot move things completely freely, because clitics like su usually must stay in second position.

So Croatian word order is flexible, but not random.

Here it means space / room.

The noun mjesto is broad and can mean different things depending on context:

• place
• spot
• seat
• room / space

In nema mjesta za veliki lonac, the natural meaning is there is no room/space for the big pot.

So this is one of those Croatian words whose exact English translation depends on context.

Because adjectives in Croatian must agree with the noun they describe.

Here the noun is:

• lonac = masculine, singular, accusative (after za)

So the adjective must also be:

• masculine
• singular
• accusative

That gives veliki lonac.

Since lonac is an inanimate masculine noun, its accusative singular looks the same as its nominative singular, which is why veliki lonac does not visibly change here.

Yes. It is very natural.

• ali = but
• opet = again / still / yet again
• nema mjesta = there is no room

So the sentence sets up a contrast:

• there are already two coasters on the table,
• but even so, there is still no space for the big pot.

This kind of structure is very common in everyday Croatian.