Relative Pronouns: Der and Som

English has one all-purpose relative pronoun for things — that — plus who, whom, and which, and it lets you drop the pronoun entirely in the book I read. Danish covers the same ground with two small words, der and som, and the single fact that decides between them is grammatical role: der can only be the subject of the relative clause, while som can be either subject or object. Get that one distinction right and roughly ninety percent of Danish relative clauses fall into place. This page also handles the leftover cases English speakers stumble on: relative hvad, clause-referring hvilket, and what happens when a preposition is involved.

The core rule: der is subject-only, som does both

A relative clause modifies a noun (the antecedent) and contains a gap — the spot where that noun would have stood inside the clause. The question is always: is the gap the subject or the object of the relative clause?

• If the gap is the subject, you may use der or som. Both are completely natural.
• If the gap is the object, you must use som (or drop it — see below). Der is impossible here.

In both of those, the gap is the subject (the man lives next door — he is doing the living), so der and som are interchangeable. Now move the gap to object position:

Here the gap is the object — I am the subject, and the book is the thing being read. Only som works. Writing bogen, der jeg læser is simply ungrammatical, the way the book what I read is in English.

Dropping the relative pronoun

When the relative word is the object, Danish — exactly like English — lets you leave it out entirely. The book I read and bogen jeg læser match word for word.

You can never drop a subject relative. The man lives next door is a doctor is wrong in English, and manden bor ved siden af os er læge is wrong in Danish for the same reason — the clause loses its subject. So the asymmetry is symmetric across the two languages: subject relatives are obligatory, object relatives are optional.

Restrictive vs non-restrictive — and the comma

A restrictive clause narrows down which thing you mean (the book that I'm reading, as opposed to the others). A non-restrictive clause just adds extra information about something already identified (my brother, who lives in Aarhus, ...). English signals the difference with commas; Danish traditionally does too, but here is the catch:

Relative hvad — 'that which', 'what'

When there is no concrete noun antecedent — when you mean the thing that — Danish uses hvad, matching English fused relative what. It often pairs with a pointing det:

Note the last pattern: det, jeg savner (literally that, I miss) is the everyday way to say what I miss, with det as the antecedent and the object pronoun dropped. You will hear it constantly.

Hvilket — referring back to a whole clause

When the relative does not point to a noun but to the entire preceding statement, Danish uses hvilket (the neuter of hvilken). English does the same job with which:

In hvilket var ret irriterende, hvilket refers to the fact that the train was late — not to any single noun. This is a B1-and-up move; in casual speech people often just start a new sentence with Det var ret irriterende, but hvilket is the tidy connector and is fully standard in writing (formal).

Relatives with a preposition

English speakers find this one fiddly because Danish strongly prefers to strand the preposition at the end of the clause, just as colloquial English does. The relative som is usually dropped:

You can keep som — huset, som jeg bor i — but the stranded preposition stays at the end either way. Danish has no natural equivalent of pulling the preposition to the front with som (you cannot say huset, i som jeg bor). The only way to front the preposition is the very formal hvilken/hvilket construction:

How this maps to English

The clean correspondences:

The biggest adjustment for an English speaker is simply remembering that Danish reserves a special word — der — for the subject slot, where English happily reuses who/that. There is no logical reason it must be der rather than som there; it is just the option Danish makes available, and many writers use it to avoid repeating som twice in one sentence.

Common Mistakes

Using der for an object gap is the single most common error, because English lets that do both jobs. Remember: der = subject only.

You may only omit the relative word when it is the object. A clause still needs a subject.

Strand the preposition at the end. Fronting it requires the formal hvilket construction, never som.

To refer back to an entire statement, use hvilket, not som and not der.

When there is no noun antecedent and you mean what / the thing that, use hvad.

Key Takeaways

• der = subject of the relative clause only. som = subject or object. When in doubt, som.
• You may drop the relative word only when it is the object (bogen jeg læser), never when it is the subject.
• Standard Danish punctuation puts a comma before relative clauses whether restrictive or not — the comma does not mark restrictiveness.
• Use hvad for what / the thing that (no noun antecedent), and hvilket to refer back to a whole clause.
• Strand prepositions at the end in everyday Danish; i hvilket is formal/literary only.

For a side-by-side decision aid see Choosing Between Der and Som, and for how relative clauses fit Danish word order see Relative Clauses.