Kad je vrijeme lijepo, sjedimo van.

Kad means when. It is very common in everyday Croatian.

Kada means the same thing, but it is the longer form. In many situations, kad sounds a bit more natural in speech, while kada can sound slightly more formal or emphatic.

So here:

• Kad je vrijeme lijepo... = When the weather is nice...

Both kad and kada would be correct here.

In this sentence, it often feels closer to whenever.

Because both verbs are in the present tense and the sentence describes a general habit, the meaning is:

• Whenever the weather is nice, we sit outside.

English may translate it as when or whenever, depending on style. Croatian kad can cover both ideas in this kind of sentence.

That is a very common question. Vrijeme can mean both time and weather.

Croatian uses the same word for both, and the context tells you which meaning is intended.

Here, because of lijepo and the whole sentence, vrijeme clearly means weather:

• vrijeme = weather

In another context, it could mean time:

• Nemam vremena. = I don’t have time.

So you have to read it from context.

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

So vrijeme can mean:

• weather
• the weather

The exact meaning comes from context, not from an article.

That is normal in Croatian. You do not need to add a separate word for the.

Because je is a clitic, and Croatian clitics normally go in the second position in their clause.

So in:

• Kad je vrijeme lijepo

the word kad comes first, and je comes immediately after it.

That is why Kad je vrijeme lijepo is natural, while Kad vrijeme je lijepo is not the normal standard order.

This is an important Croatian word-order pattern:

• Kad je...
• Ako je...
• Dok je...

Because lijepo agrees with vrijeme.

The noun vrijeme is:

• singular
• neuter
• nominative here

So the adjective must also be neuter singular:

• lijepo vrijeme = nice weather
• vrijeme je lijepo = the weather is nice

Compare:

• dan je lijep = the day is nice
• noć je lijepa = the night is nice
• vrijeme je lijepo = the weather is nice

Here it is an adjective.

It describes the noun vrijeme, even though it comes after the verb je:

• vrijeme je lijepo = the weather is nice

So lijepo is agreeing with vrijeme, which is why it has the neuter form.

If you say just Kad je lijepo, that is a slightly different structure, closer to When it is nice out.

Yes. That is also correct and very natural.

Compare:

• Kad je vrijeme lijepo, sjedimo van.
• Kad je lijepo vrijeme, sjedimo van.

Both mean essentially the same thing.

The difference is structural:

• vrijeme je lijepo = the weather is nice
• lijepo vrijeme = nice weather

So the first version uses a predicate adjective, and the second uses an adjective + noun phrase.

Sjedimo is the present-tense form meaning we sit or we are sitting.

It comes from the verb sjediti, which means to sit or to be sitting.

Here, because the sentence describes a usual situation, sjedimo is best understood as:

• we sit outside
• we sit outside when the weather is nice

So this is more about a habit than about one single moment.

Because sjediti and sjesti / sjesti down are different ideas.

• sjediti = to sit / to be sitting
• sjesti or sjesti down = to sit down (the action of taking a seat)

So:

• sjedimo van = we sit outside / we are sitting outside
• sjednemo van would suggest we sit down outside

In this sentence, the focus is on being seated outside as a usual thing, not on the moment of sitting down. That is why sjedimo is the right choice.

Croatian often leaves out subject pronouns, because the verb ending already shows who the subject is.

• sjedim = I sit
• sjediš = you sit
• sjedimo = we sit

So sjedimo already includes the idea of we.

You can say mi sjedimo if you want emphasis, but it is not necessary here.

Van means outside or out.

Yes, you can also say vani in many situations. Both are common.

So these are both natural:

• sjedimo van
• sjedimo vani

Very roughly:

• van can feel a bit shorter and more conversational
• vani is also very common and clear as outside

You will hear both from native speakers.

Because Kad je vrijeme lijepo is a subordinate clause at the beginning of the sentence.

Croatian normally separates that kind of opening clause with a comma:

• Kad je vrijeme lijepo, sjedimo van.

This is similar to English:

• When the weather is nice, we sit outside.

So the comma is standard here.

Yes, absolutely. That is very natural Croatian.

• Kad je lijepo, sjedimo van. = When it’s nice out, we sit outside.

In that version, vrijeme is omitted because it is understood from context. Croatian often does this with weather expressions.

So:

• Kad je vrijeme lijepo... = more explicit
• Kad je lijepo... = shorter and very common

Not with exactly the same nuance.

• kad = when / whenever
• ako = if

So:

• Kad je vrijeme lijepo, sjedimo van.
  = When/Whenever the weather is nice, we sit outside.

But:

• Ako je vrijeme lijepo, sjedimo van.

sounds more like a condition, closer to If the weather is nice, we sit outside.

In English, when and if can sometimes overlap a little, but in Croatian the choice affects the meaning more clearly. Here kad is the better choice for a repeated, usual situation.