When the noun you are describing is a thing and it sits after a preposition, Dutch refuses to use die or dat. You cannot say "the chair on which I sit" with op die or "the book about which we talk" with over dat. Instead Dutch reaches for a special construction built on the word waar: de stoel *waarop ik zit, het boek **waarover we praten. This page shows you exactly how to build it, why it exists, and how it mirrors the pronominal-adverb system (*daarop, daarover) you may already know.
The core rule: thing + preposition → waar + preposition
In English, a relative clause with a preposition has three shapes: the chair on which I sit, the chair that I sit on, or simply the chair I sit on. Dutch collapses all of these into one mechanism. Whenever the antecedent is a thing (not a person) and a preposition is involved, you fuse waar with that preposition into a single word:
| Preposition | waar-form | Example phrase | English |
|---|---|---|---|
| op (on) | waarop | de stoel waarop ik zit | the chair I'm sitting on |
| over (about) | waarover | het boek waarover we praten | the book we're talking about |
| in (in) | waarin | het huis waarin ze woont | the house she lives in |
| met (with) | waarmee | de pen waarmee ik schrijf | the pen I write with |
| naar (to/at) | waarnaar | de film waarnaar we kijken | the film we're watching |
| aan (on/about) | waaraan | het project waaraan ik werk | the project I'm working on |
Dit is de stoel waarop ik altijd zit.
This is the chair I always sit on.
Het boek waarover we het hadden, ligt nog op je bureau.
The book we were talking about is still on your desk.
Dat is de pen waarmee ik mijn examen heb gemaakt.
That's the pen I took my exam with.
Notice that the conjugated verb still lands at the end of the relative clause — a relative clause is a subordinate clause, so verb-final order applies exactly as it does after die and dat.
Two prepositions change shape: met → mee, tot → toe
Two prepositions never appear in their plain form inside this construction. Met becomes mee, and tot becomes toe. This is not optional and not regional — it is fixed. So "the pen I write with" is de pen *waarmee ik schrijf, never *waarmet.
De hamer waarmee hij het slot heeft opengebroken, lag in de tuin.
The hammer he broke the lock open with was lying in the garden.
Het doel waartoe alles leidt, is nog onduidelijk.
The goal everything leads up to is still unclear. (literary)
Splitting is allowed — and very common in speech
The fused form waarop, waarover, waarmee can be split apart. The waar stays at the front of the relative clause (right after the antecedent), and the preposition slides to a spot just before the verb cluster at the end. Both versions mean exactly the same thing.
de stoel waarop ik zit
the chair I'm sitting on (fused — neutral, slightly more formal in writing)
de stoel waar ik op zit
the chair I'm sitting on (split — extremely common in everyday speech)
Dat is het probleem waar ik de hele week al over nadenk.
That's the problem I've been thinking about all week. (split — natural conversational Dutch)
In spoken Dutch the split version is the default; native speakers split waar from its preposition constantly. The fused version is a touch more formal and is the safer choice in careful writing, but neither is wrong. When the relative clause is long, splitting actually reads more smoothly, because it spreads the construction across the clause instead of front-loading a heavy waarover/waaraan.
Why waar, and not "op die"? The parallel with daarop
The reason Dutch uses waar here is the same reason it uses daar in pronominal adverbs. Dutch strongly resists putting a non-personal pronoun directly after a preposition. You don't say op het or met dat to mean "on it" / "with that"; you say erop, daarmee. The pieces flip and fuse: preposition + it/that → er-/daar- + preposition.
The relative system simply borrows the question/relative member of that same series, waar-:
| Meaning | Word | Example |
|---|---|---|
| on it | erop | Er ligt een boek erop. → Daar ligt een boek op. |
| on that | daarop | Ik reken daarop. |
| on what / on which | waarop | de tafel waarop het ligt |
So the logic is fully systematic: daar points back to a known thing, waar opens a question or a relative clause about a thing. Both fuse with the preposition, both can split. Once you see waarop as the relative twin of daarop, the whole construction stops feeling arbitrary.
De kast waarin ik mijn papieren bewaar, is op slot.
The cabinet I keep my papers in is locked.
Het onderwerp waarover de docent het had, komt op het tentamen.
The topic the lecturer talked about will be on the exam. (academic)
Things use waar-; persons use prep + wie
This is the dividing line you must keep sharp. For a thing, you use waar + preposition. For a person, you use the preposition followed by wie. Never mix them.
| Antecedent | Construction | Example |
|---|---|---|
| thing | waar + prep | de man waarmee… ❌ → het mes waarmee… ✅ |
| person | prep + wie | de man met wie ik praat ✅ |
De collega met wie ik samenwerk, gaat met pensioen.
The colleague I work with is retiring. (person → met wie)
Het programma waarmee ik werk, loopt steeds vast.
The software I work with keeps crashing. (thing → waarmee)
You can sometimes hear waarmee used for a person in very casual speech, and even waarop for a person, but in careful Dutch this is considered an error — persons take wie. When in doubt, ask yourself: is the antecedent a human? If yes, prep + wie; if no, waar + prep.
Common Mistakes
❌ de stoel op die ik zit
Incorrect — you can't put a non-personal relative after a preposition; use waar + prep.
✅ de stoel waarop ik zit / de stoel waar ik op zit
the chair I'm sitting on
❌ het mes met dat ik snijd
Incorrect — 'met dat' for a thing is impossible; met fuses into waarmee.
✅ het mes waarmee ik snijd / het mes waar ik mee snijd
the knife I cut with
❌ de vriend waarmee ik op vakantie ga
Incorrect — a person takes prep + wie, not a waar-form.
✅ de vriend met wie ik op vakantie ga
the friend I'm going on holiday with
❌ de pen waarmet ik schrijf
Incorrect — 'met' must become 'mee' in this construction.
✅ de pen waarmee ik schrijf
the pen I write with
❌ het boek waarover we praten erover
Incorrect — don't double the preposition; waarover already contains 'over'.
✅ het boek waarover we praten
the book we're talking about
Key Takeaways
- A thing after a preposition in a relative clause takes waar + preposition: waarop, waarover, waarin, waaraan.
- met → mee and tot → toe inside this construction; waarmee, waartoe, never waarmet/waartot.
- The form can be fused (waarop ik zit) or split (waar ik op zit); splitting is the spoken default.
- It is the relative twin of the pronominal adverbs daarop / erop — Dutch never puts a non-personal pronoun straight after a preposition.
- Persons take prep + wie (met wie), not a waar-form. Keep the person/thing split sharp.
Now practice Dutch
Reading grammar gets you part of the way. The exercises are where it sticks — free, no signup needed.
Start learning Dutch→Related Topics
- Dutch Relative Clauses: OverviewB1 — How Dutch attaches a who/which/that clause to a noun — the pronoun agrees with the noun's gender and number, and the verb is banished to the end of the clause.
- Wie: Relatives for People after a PrepositionB2 — When a relative pronoun referring to a person is governed by a preposition, Dutch uses preposition + wie — met wie, aan wie, op wie — and never waar- or die.
- Wat as a Relative PronounB2 — When Dutch uses wat instead of dat or die — after alles/iets/niets, after a neuter superlative, after dat, and when the antecedent is a whole clause.
- Pronominal Adverbs: Erop, Daarmee, WaaroverB1 — When a preposition's object is a thing (not a person), Dutch does not say 'op het' or 'met dat' — it fuses the pronoun and preposition into a single pronominal adverb: erop, hierin, daarmee, waarover, daarnaar. Covers the er/hier/daar/waar paradigm, the irregular fusions (met → mee, tot → toe), the splitting that scatters the two halves across the clause, and why questions and relative clauses need waar-forms.
- Pronominal Er: Er + Preposition (ermee, erop, erover)B1 — A preposition cannot take a thing-pronoun in Dutch, so er replaces it and fuses with the preposition — 'with it' is ermee, not 'met het'; 'about it' is erover; 'on it' is erop — with the irregular fusions met→mee and tot→toe.
- Verb-Final Order in Subordinate ClausesA2 — After a subordinating conjunction, relative pronoun, or question word, the entire verb cluster — including the finite verb — moves to the end of the clause.