Når gæsterne kommer, sætter jeg vasen på bordet i stuen.

Når means when in the sense of something that happens whenever or when it happens in the future.

In this sentence, Når gæsterne kommer means When the guests arrive / When the guests come.

A learner often compares når with da:

• når = when, for repeated events or future events
• da = when, for a specific event in the past

So here når is used because the sentence refers to a future situation.

Danish often uses the present tense to talk about the future, especially when the time is already clear from the context.

So:

• Når gæsterne kommer = When the guests come / arrive
• not necessarily a present-time event, even though the verb is in present tense

This is very normal in Danish. English can do something similar in time clauses:

• When the guests come, I’ll put the vase on the table.

Notice that English also uses come, not will come, after when.

This is because Danish follows the V2 rule in main clauses: the finite verb normally comes in the second position.

The sentence begins with a subordinate clause:

• Når gæsterne kommer

After that, the main clause starts, and the verb must come before the subject:

• sætter jeg vasen på bordet i stuen

So the structure is:

• subordinate clause
• verb
• subject
• rest of the sentence

Compare:

• Jeg sætter vasen på bordet i stuen.
• Når gæsterne kommer, sætter jeg vasen på bordet i stuen.

That word order change is very important in Danish.

Gæsterne means the guests.

It comes from:

• en gæst = a guest
• gæster = guests
• gæsterne = the guests

Danish usually adds the definite article to the end of the noun instead of using a separate word like the.

So:

• gæst = guest
• gæsten = the guest
• gæster = guests
• gæsterne = the guests

Because Danish often marks definiteness with an ending on the noun.

• en vase = a vase
• vasen = the vase

So vasen already includes the meaning of the.

This is one of the most basic features of Danish nouns:

• common gender singular definite: often -en
• neuter singular definite: often -et
• plural definite: often -ne

Here:

• vase is a common gender noun
• so vasen = the vase

Bordet means the table.

It comes from:

• et bord = a table
• bordet = the table

Unlike vase, which is common gender (en vase), bord is a neuter noun (et bord). That is why the definite form ends in -et instead of -en.

So:

• en vase → vasen
• et bord → bordet

Because i means in, and stuen is treated here as a room you are in.

So:

• i stuen = in the living room

The phrase på bordet uses på because something is on the table.

So the sentence has two location phrases:

• på bordet = on the table
• i stuen = in the living room

That is completely natural: the vase is on something, and that thing is in a room.

Stuen means the living room.

The base form is:

• en stue = a living room / sitting room / room

And:

• stuen = the living room

In everyday Danish, stue often refers to the main living room of a home.

Be careful: in some contexts, stuen can also mean the ground floor, depending on the situation. But in this sentence, with på bordet i stuen, it clearly means the living room.

This is a normal Danish sentence structure. After the verb and subject, Danish often places:

1. the object
2. then adverbials such as place or time

Here:

• sætter = put/place
• jeg = I
• vasen = the vase
• på bordet i stuen = on the table in the living room

So the order is very natural: verb + subject + object + location

You could sometimes move elements for emphasis, but the sentence as given is standard and neutral.

It can be understood as either come or arrive, depending on the translation style.

• gæsterne kommer literally = the guests come
• in natural English, this often becomes the guests arrive

So both ideas are present. The Danish verb komme often covers situations where English might prefer come or arrive.

Yes, and this is a good question because Danish has several placement verbs.

Sætter comes from at sætte, which often means to set, put, or place. It is commonly used when placing something in an upright or settled position.

With a vase, sætte is very natural:

• Jeg sætter vasen på bordet. = I put/set the vase on the table.

Other Danish verbs for putting things somewhere include:

• lægge = lay/put something down, often horizontally
• stille = place/stand something upright
• sætte = set/put, often for many ordinary placement situations

In real usage, stille vasen på bordet is also something you may hear, because a vase stands upright. But sætte is also perfectly idiomatic.

Yes. Når gæsterne kommer is a subordinate clause introduced by når.

Inside that clause, the word order is the ordinary subject-verb order:

• gæsterne = subject
• kommer = verb

Then the main clause follows:

• sætter jeg vasen på bordet i stuen

This distinction matters because Danish word order changes in the main clause after an opening subordinate clause.

A rough English-friendly guide:

• gæsterne ≈ GES-ter-neh, but with a Danish vowel that does not exist exactly in English
• sætter ≈ SEH-ter, again with a special Danish vowel

A few notes:

• æ is a very common Danish vowel, somewhat like the vowel in English cat, but not exactly the same
• the r in Danish is softer than in most English accents
• final -e in gæsterne is not silent the way English learners may expect

If you want to sound more natural, it helps to listen to native audio, because Danish vowels are difficult to learn from spelling alone.

Yes:

Jeg sætter vasen på bordet i stuen, når gæsterne kommer.

That means the same thing: I put the vase on the table in the living room when the guests arrive.

The difference is mainly in emphasis and rhythm.

• Når gæsterne kommer, sætter jeg ... puts the time condition first
• Jeg sætter ..., når gæsterne kommer starts with the action

Both are natural. The important grammar difference is that when the subordinate clause comes first, the main clause has inversion:

• sætter jeg

But when the main clause comes first, you keep normal order:

• jeg sætter

It can be understood either way, depending on context.

Because Danish uses present tense here, the sentence could mean:

• a habitual action: Whenever the guests come, I put the vase on the table in the living room
• a planned future action: When the guests come, I’ll put the vase on the table in the living room

The context would tell you which meaning is intended. Without more context, both are possible.