Learn Hardcore Danish: Jeg har to bøger i rummet.

In this sentence you mean a specific room, so you say i rummet = in the room.
Just i rum would sound wrong in this context (it can mean in space in other contexts, though).

Why isn’t there a separate word for the before rummet?

Danish usually puts the at the end of the noun, as a suffix, not as a separate word:

Common gender:
- en bog = a book → bogen = the book
Neuter gender:
- et rum = a room → rummet = the room

So rum + et becomes rummet.
That’s why you don’t say i det rum in normal speech, but i rummet. (You can say i det rum with special emphasis: in that room).

What’s going on with bøger? Why isn’t it just boger?

Bøger is an irregular plural of bog (book).

The pattern is:

en bog = a book (singular, indefinite)
bogen = the book (singular, definite)
bøger = books (plural, indefinite)
bøgerne = the books (plural, definite)

Two things happen in the plural:

The vowel changes: o → ø (bog → bøger)
You add -er to make the plural: bøg‑er → bøger

So to bøger literally = two books.

Why is there no word like a before bøger? In English I’d say “two books”, not “two the books” — is it the same in Danish?

Yes, it works the same way.

In Danish you don’t use an article (a/the) when you have a number in front of a countable noun:

✅ to bøger = two books
❌ to en bøger (wrong)
❌ to bøgerne (wrong if you just mean two books; it would mean the two books in the right context)

Forms again:

en bog = a book
bogen = the book
bøger = books
bøgerne = the books / the … books

So Jeg har to bøger is directly parallel to I have two books.

Could I also say Der er to bøger i rummet? What’s the difference from Jeg har to bøger i rummet?

Yes, you can say both, but there’s a nuance:

Jeg har to bøger i rummet.
- Focus on me as the owner/possessor.
- Implies the two books are my books (or at least under my control) and they are located in the room.
Der er to bøger i rummet. = There are two books in the room.
- Neutral existence/location.
- Just states that two books are present in the room; says nothing about whose they are.

In many contexts both are possible, but Der er… is the normal way to simply say that something exists/stands/lies somewhere.

Can the word order change? Could I say I rummet har jeg to bøger?

Yes, that’s correct Danish, and it slightly changes the emphasis.

Danish main clauses are generally verb-second (V2). Some options:

Jeg har to bøger i rummet.
- Neutral, subject-first.
- Order: Subject (Jeg) – Verb (har) – Object (to bøger) – Place (i rummet).
I rummet har jeg to bøger.
- Puts emphasis on the place (In the room, I have two books).
- Order: Place (I rummet) – Verb (har) – Subject (jeg) – Object (to bøger).

What you cannot do in neutral speech is something like:

❌ Jeg har i rummet to bøger (feels awkward and very marked, if not wrong, to a native ear in most contexts).

Why does har look the same with different subjects? Shouldn’t it change like in English (I have / he has)?

Danish present tense verbs do not change with the subject:

jeg har = I have
du har = you have
han/hun har = he/she has
vi har = we have
I har = you (plural) have
de har = they have

Same form, har, for all persons.

Only the tense changes:

har = have / has (present)
havde = had (past)

Does har here mean just “to possess”, or is it also that helper verb used for past tense?

In this sentence har is the main verb meaning to have / to possess:

Jeg har to bøger i rummet. = I have/own/possess two books (which are in the room).

But har is also used as an auxiliary verb to form the perfect tense:

Jeg har læst bogen. = I have read the book.
Hun har købt en bog. = She has bought a book.

So har can be:

A main verb (to have), as in your sentence.
An auxiliary (have in have done), followed by a past participle.

Why is the preposition i used here and not på?

Very roughly:

i = in, inside (within boundaries)
på = on, on top of, at (surface or certain locations)

For being inside a room, Danish normally uses i:

i rummet = in the room
i huset = in the house
i bilen = in the car

på is used with surfaces and some fixed expressions:

på bordet = on the table
på skolen = at (the) school
på arbejde = at work

So i rummet is the standard way to say in the room.

Is there a difference between rum and værelse in Danish?

Yes, there is a nuance:

rum
- General word for room / space / chamber.
- Can be any kind of room (living room, room in a building, empty space, etc.).
- More neutral and technical.
værelse
- More like bedroom or private room (also a hotel room, student room, etc.).
- Often implies a room someone lives or sleeps in.

So:

Jeg har to bøger i rummet.
- In the (unspecified) room / in that room.
Jeg har to bøger på værelset.
- In my (bed)room (typical everyday phrase).

Both are correct, but they don’t always describe the same kind of room.

How do you pronounce Jeg har to bøger i rummet?

A fairly standard Danish pronunciation (simplified) is:

Jeg ≈ yai (IPA: [jɑj] or [jaj])
har ≈ haar with a little catch at the end (IPA: [hɑːˀ])
to ≈ toe (long o) (IPA: [tˢoː])
bøger ≈ something like BUR-yer but with rounded lips on bø (IPA: [ˈbøːjɐ] / [ˈbøːɐ])
i ≈ ee (IPA: [iː])
rummet ≈ RUM-eth with a very soft final d (almost not heard) (IPA: [ˈʁɔmˀəð] or similar, varies by accent)

Spoken fairly naturally, it runs together something like:

“Yai haar toe BUR-yer ee RUM-eth.”

Danish often “swallows” sounds, especially final consonants and d, so expect it to sound more blurred than the spelling suggests.