Relative Clauses

A relative clause is a clause that modifies a noun — "the man who lives next door", "the house I bought", "the chair you're sitting on". Danish builds these with der and som, and the grammar has three features that surprise English speakers: the choice between der and som depends on the grammatical role of the relative word, the relative word is often dropped entirely, and — most strikingly — Danish strands its prepositions at the end of the clause as the normal, everyday pattern. This page is about how the clause is built and where the preposition goes. For a closer look at the forms of der and som themselves, see pronouns/relative-der-som.

Relative clauses follow subordinate-clause word order

Before anything else: a relative clause is a subordinate clause, so it obeys subordinate word order. That means sentence adverbs come before the finite verb, exactly as in syntax/subordinate-clauses.

Notice der ikke kom, not der kom ikke. The ikke sits in front of the verb because we are inside a subordinate clause. This is the same flip you learned for at- and fordi-clauses, applied here.

Der: subjects only

When the relative word is the subject of its own clause — the one doing the verb — Danish can use der.

Here der stands for en kollega and is the subject of taler. You could also use som in this position (en kollega, som taler fem sprog), and many speakers do. But the reverse is not allowed: der is only ever a subject. The moment the relative word is an object, der is impossible.

A useful rule of thumb: if the verb in the relative clause has its own separate subject, the relative word is an object, and you cannot use der. If the relative word is the subject, der is fine.

Som: subjects or objects — and droppable as an object

Som is the all-purpose relative word. It works as a subject (interchangeable with der) and as an object (where der is banned).

As a subject:

As an object, som refers to the thing the verb is done to, and the clause has its own subject:

Here som = filmen, vi is the subject doing the seeing, and som is the object of så. And now the most useful economy in Danish relative clauses: when som is the object, you can simply leave it out. Both versions are completely natural; dropping it is, if anything, more common in speech.

This will feel familiar to English speakers — English also drops the object relative ("the film we saw"). The thing to internalise is when you can drop it: only when som is an object. A subject relative can never be dropped:

Prepositional relatives: Danish strands the preposition

Here is where Danish parts company most sharply from the formal grammar many learners were taught. When the relative word is the object of a preposition — "the house I live in", "the friend I talked to" — everyday Danish leaves the preposition stranded at the end of the clause, exactly where it would sit in a normal sentence. The relative word is som, and it can be dropped just like any other object relative.

Read those again and notice the rhythm: the preposition (i, med, på) sits at the very end, hanging off the verb, just as it would in the plain statement Jeg bor i huset. Stranding is not casual or sloppy — it is the default, native pattern across all registers of spoken and most written Danish.

Pied-piping is bookish and usually wrong-sounding

The alternative — pulling the preposition to the front along with a relative word, the construction grammar calls pied-piping — exists in Danish but is heavily formal, even archaic, and uses a different relative form (hvilket/hvilken or hvem after the preposition, never som). Constructions like i hvilket hus jeg bor ("in which house I live") belong to legal documents and nineteenth-century prose, not conversation. This is the exact reverse of what learners with a formal grammar background expect: they were often taught that ending a sentence with a preposition is "wrong," so they reach for the front-loaded version — and in Danish that makes them sound like a contract.

Restrictive vs non-restrictive: it's about the comma

A relative clause can be restrictive (it narrows down which noun you mean — essential information) or non-restrictive (it adds a side remark about an already-identified noun). The distinction matters for the comma.

In a non-restrictive clause, the noun is already pinned down and the relative clause just adds extra information. It is set off by commas, and in speech by a slight pause:

You have only one sister; som bor i Aarhus is bonus information, not identification. The commas (and pauses) signal that.

In a restrictive clause, the relative clause is doing essential work — telling you which one — and in careful writing the trend is to omit the comma to mark it as restrictive:

Here der kører til lufthavnen identifies which bus among many; it is restrictive.

A caveat worth stating honestly: Danish comma rules around relative clauses are genuinely contested. The official Dansk Sprognævn allows two systems — a traditional "grammatical comma" that brackets every subordinate clause, and a newer "comma-light" (nyt komma / pause-based) practice that distinguishes restrictive from non-restrictive much as English does. Many Danes mix the two. So while the restrictive/non-restrictive meaning is real and important, you will see the commas placed inconsistently in the wild. Aim for the meaning — pauses in speech, commas around genuine side-remarks in writing — and don't be thrown when published Danish doesn't follow it perfectly.

The three patterns in one view

Three roles, one principle: der is reserved for subjects, som covers everything, and as an object — including the object of a stranded preposition — som can simply vanish.

Common Mistakes

The clause already has its own subject (vi), so the relative word is an object — der is impossible. Use som, or drop it entirely.

This is grammatically possible but sounds like a legal contract. The natural pattern leaves i at the end. Learners taught "never end on a preposition" reliably get this backwards in Danish.

Only object relatives can be omitted. When the relative word is the subject, you must keep der or som. (Note der aldrig ringer — aldrig before the verb, subordinate order.)

Some learners (especially from languages that use resumptive pronouns) insert an extra den or det to "fill" the relative word's old slot. Danish does not do this — the relative word already fills the role.

You may drop som, but you may never drop the stranded preposition. Sidde på needs its på; without it, the sentence is incomplete. Drop the relative word if you like — keep the preposition.

Key Takeaways

• Relative clauses are subordinate clauses: sentence adverbs go before the verb (der ikke kom).
• der = subject only; som = subject or object. der can never be an object.
• An object som — including the object of a preposition — can be dropped: filmen (som) vi så, huset (som) jeg bor i. A subject relative cannot be dropped.
• Everyday Danish strands the preposition at the end (som jeg bor i); pied-piping (i hvilket hus) is formal and rare — the opposite of what "don't end on a preposition" training suggests.
• Restrictive vs non-restrictive is a real meaning distinction (essential vs side-remark), but Danish comma practice around it is officially split — follow the sense, and expect inconsistency in published text.