Learn Hardcore Croatian: Kad redovito čistimo stan, stol je rjeđe prljav. - When we clean the apartment regularly, the table is dirty less often.

Even though in English you might think in terms of “if we clean” or “when we (do) clean”, Croatian simply uses the present to express this kind of general truth or repeated situation.

The same pattern appears in other habitual sentences:

Kad radim od kuće, pijem više kave.
When(ever) I work from home, I drink more coffee.

Is there any difference between "kad" and "kada" in this sentence?

Functionally, no real difference here.

kad – more common in everyday speech, shorter, slightly more informal
kada – a bit more formal or emphatic, often used in writing or when you want to sound careful/clear

You could say:

Kad redovito čistimo stan, stol je rjeđe prljav.
Kada redovito čistimo stan, stol je rjeđe prljav.

Both are correct and mean the same thing. In normal speech, you’ll hear kad more often.

Why is it "čistimo" and not a future tense like "čistit ćemo"?

Because the sentence describes a general, repeated habit, not a specific future plan.

čistimo = we clean (present, habitual/regular)
čistit ćemo = we will clean (future, a particular future action or plan)

Using the future here would sound off or too specific, like you’re focusing on one future period:

✗ Kad ćemo redovito čistiti stan, stol će biti rjeđe prljav. – grammatically possible, but sounds clumsy and unnatural for stating a general rule.

For general rules and habits in “when… then…” sentences, Croatian almost always uses the present on both sides, just like here.

Why is "stan" in this form, and why is there no article or preposition?

Croatian does not have articles (a / an / the), so you just say stan and the meaning “the apartment / our apartment” is understood from context.

Grammatically:

stan is a masculine singular noun
Here it is the direct object of čistimo (we clean), so it is in the accusative case

For masculine inanimate nouns like stan, the accusative singular has the same form as the nominative singular:

Nominative (subject): Stan je velik. – The apartment is big.
Accusative (object): Čistimo stan. – We clean the apartment.

No preposition is needed because čistiti simply takes a direct object.

Can the word order in "Kad redovito čistimo stan" be changed?

Yes, to a degree. Croatian word order is flexible, and you can move words around to change or fine‑tune emphasis.

Some possible variants:

Kad redovito čistimo stan, stol je rjeđe prljav. – neutral, standard.
Kad čistimo stan redovito, stol je rjeđe prljav. – still okay, redovito is slightly more emphasized.
Kad stan redovito čistimo, stol je rjeđe prljav. – emphasizes stan a bit (it’s the apartment we clean regularly).

All of these are understandable. The original version is the most natural and “textbook” one.

What is the difference between "redovito" and "redovno"?

Both are adverbs meaning “regularly”, and in this sentence you could use either:

Kad redovito čistimo stan…
Kad redovno čistimo stan…

Nuances:

redovito – somewhat more standard / neutral form
redovno – very common in everyday speech, depending on region

You will hear both; they are usually interchangeable.

What exactly does "rjeđe" mean, and what is its base form?

rjeđe is the comparative form of the adverb rijetko.

rijetko = rarely, seldom
rjeđe = more rarely, less often
(i.e. something happens not as often as before / as in some other situation)

In this sentence:

stol je rjeđe prljav
= the table is dirty less often / the table is dirty more rarely

The forms are:

Positive: rijetko – rarely
Comparative: rjeđe – less often / more rarely
Superlative: najrjeđe – the most rarely, least often

Note the spelling change rije- → rje- in the comparative (rijetko → rjeđe).

Could we also say "stol je manje prljav" here? Would it mean the same thing?

No, it would not mean the same thing.

stol je rjeđe prljav
→ focus on frequency: the table is dirty less often (it’s dirty on fewer occasions)
stol je manje prljav
→ focus on degree/intensity: the table is less dirty (it has less dirt when it is dirty)

So:

If you mean “not dirty so often anymore”, use rjeđe prljav.
If you mean “it still gets dirty, but not as dirty as before”, you’d say manje prljav.

Why is "prljav" in this form, and how does it agree with "stol"?

prljav is an adjective meaning “dirty”.

In Croatian, adjectives must agree with the nouns they describe in:

Gender
Number
Case

Here:

stol = masculine, singular, nominative (subject of je)
therefore prljav is also masculine, singular, nominative

So we get:

stol je prljav – the table is dirty
stol je rjeđe prljav – the table is dirty less often

If the noun changed, the adjective would change too:

stolica je rjeđe prljava. – The chair is dirty less often. (feminine sg: prljava)
podovi su rjeđe prljavi. – The floors are dirty less often. (masculine plural: prljavi)

Where can "rjeđe" be placed in the second part? Is "Stol je rjeđe prljav" the only possible order?

The given order is the most natural:

Stol je rjeđe prljav.

Other possibilities exist but sound different or less natural:

Rjeđe je stol prljav.
– Emphasizes rjeđe strongly: It’s less often that the table is dirty. More stylistic, slightly marked.
Stol je prljav rjeđe.
– Possible, but sounds a bit awkward and is rarely used; the adverb usually comes before the adjective in such patterns.

So in normal speech and writing, “Stol je rjeđe prljav” is the best choice.

Do we need the verb "je" here? Can we just say "stol rjeđe prljav"?

Yes, you need the verb je.

In Croatian, when you state what something is (X is Y), you normally must use the copula (form of biti = to be):

stol je prljav – the table is dirty
stol je rjeđe prljav – the table is dirty less often

You cannot say:

✗ stol rjeđe prljav

That is ungrammatical as a full sentence. The only context where je disappears is in very short answers or colloquial ellipsis:

Kakav je stol? – What is the table like?
– Prljav. – [It’s] dirty.

Why is there a comma between the two parts of the sentence?

Because the sentence has:

a subordinate clause introduced by kad:
Kad redovito čistimo stan
followed by the main clause:
stol je rjeđe prljav.

In Croatian, when a subordinate clause comes first, you normally separate it with a comma:

Kad završim posao, idem kući.
Ako pada kiša, ostajemo doma.
Kad redovito čistimo stan, stol je rjeđe prljav.

If the main clause comes first, you still usually keep the comma:

Stol je rjeđe prljav, kad redovito čistimo stan.

In everyday speech, people may pause or not, but in standard writing the comma is required here.