English speakers do something every day that German flatly forbids: they leave a preposition stranded at the end of a clause. "Who are you talking to?" "That's the film I've been waiting for." "What are you thinking about?" In each, the preposition sits orphaned at the end, far from the word it belongs with. German does not allow this — ever. The preposition must stay glued to its pronoun, and the two travel together. Either the whole prepositional phrase moves to the front (this is called pied-piping), or, when the object is a thing, the preposition fuses with wo- or da- into a single compound word. There is no third option and no clause-final dangling. This is one of the most natural English habits to carry over, and one of the most reliably wrong.
The rule: the preposition never strands
A German preposition forms a tight unit with the word it governs. When that word is a question word or a relative pronoun and has to move to the front of the clause, the preposition is pied-piped — dragged along with it. The English option of leaving it behind simply does not exist.
Mit wem sprichst du?
Who are you talking to? Literally 'With whom are you speaking?' — the preposition 'mit' moves to the front with 'wem'.
Für wen ist das Geschenk?
Who's the present for? 'für' travels with 'wen' to the front; it cannot strand at the end.
Auf wen wartest du?
Who are you waiting for? 'auf wen' moves together; '*Wen wartest du auf?' is impossible.
The phrase that English splits — "who … to," "who … for," "who … about" — German keeps in one piece at the front: mit wem, für wen, über wen. The interrogative pronoun takes the case the preposition demands (mit + dative → wem; für + accusative → wen), and the whole unit fronts as one.
Things take wo-compounds, not prepositions + pronoun
Pied-piping with wem/wen/wer works for people. But when the object is a thing or an idea, German does not say über was or auf was in careful usage. Instead it fuses the preposition with wo- into a single interrogative compound: worüber, worauf, womit, wovon, wofür.
Worüber redet ihr?
What are you talking about? 'über' + 'wo' → 'worüber'; the English stranded 'about' becomes part of one German word.
Womit hast du das geöffnet?
What did you open that with? 'mit' fuses into 'womit' — no stranding, no separate pronoun.
Wovon sprichst du eigentlich?
What are you actually talking about? 'von' + 'wo' → 'wovon'.
Here is the orthographic detail that trips people up: when the preposition begins with a vowel, German inserts a linking -r- to ease pronunciation. So auf + wo is worauf (not wowauf or woauf); über + wo is worüber; an + wo is woran. With consonant-initial prepositions there is no -r-: mit → womit, von → wovon, für → wofür.
| Preposition | wo-compound (questions) | da-compound (statements) |
|---|---|---|
| mit | womit | damit |
| von | wovon | davon |
| für | wofür | dafür |
| auf (vowel → +r) | worauf | darauf |
| über (vowel → +r) | worüber | darüber |
| an (vowel → +r) | woran | daran |
The same fusion happens in statements with da- when you refer back to a thing: Ich freue mich darauf ("I'm looking forward to it"), Ich denke oft daran ("I often think about it"). People get a personal pronoun (auf ihn, an sie); things get the *da-*compound.
Relative clauses: pied-piping again
The same principle governs relative clauses. A preposition that belongs to the relative pronoun fronts with it to the start of the relative clause — never to the end.
Der Mann, mit dem ich rede, ist mein Chef.
The man I'm talking to is my boss. 'mit dem' opens the relative clause; English strands the 'to'.
Die Frau, für die ich arbeite, ist sehr nett.
The woman I work for is very nice. 'für die' moves to the front of the relative clause as a unit.
Das Thema, über das wir gesprochen haben, war heikel.
The topic we talked about was tricky. 'über das' fronts together; the preposition cannot dangle.
For things, the relative clause can also use a wo-compound as a more compact (and slightly more formal/written) alternative: das Thema, worüber wir gesprochen haben. Both the pied-piped über das and the fused worüber are correct for inanimate referents; for people, only the pied-piped über den/die is available.
Das Projekt, woran wir arbeiten, ist fast fertig.
The project we're working on is almost finished. 'woran' (an + wo + linking r) heads the relative clause.
The English contrast in one line
English has two strategies, German has two strategies, but they barely overlap. English may strand ("the man I work for") or, more formally, pied-pipe ("the man for whom I work"). German may pied-pipe ("der Mann, für den ich arbeite") or use a wo-compound for things ("das Thema, worüber..."). The one option English uses most — stranding — is the one option German never permits.
| Meaning | English (common) | German (correct) |
|---|---|---|
| Who are you talking to? | preposition stranded | Mit wem sprichst du? |
| What are you waiting for? | preposition stranded | Worauf wartest du? |
| the film I'm waiting for | stranded | der Film, auf den ich warte |
| the topic we talked about | stranded | das Thema, worüber wir reden |
The distinguishing insight
The single thing to internalise: "the thing I'm waiting for" has two correct German forms and zero stranded forms. You may pied-pipe — auf das ich warte — or fuse — worauf ich warte — but you can never write ... das ich warte auf. There is no German sentence that ends with an orphaned preposition belonging to a fronted pronoun. The moment you feel the English urge to push the preposition to the end, that is the signal to do the opposite: pull it to the front.
Common Mistakes
Stranding the preposition in a question — the most natural English transfer error.
❌ Wem redest du mit?
Incorrect — the preposition cannot strand; it must front with the pronoun: 'Mit wem redest du?'.
✅ Mit wem redest du?
Who are you talking to?
Stranding in a relative clause.
❌ Der Film, den ich mich freue auf.
Incorrect — the preposition 'auf' is stranded; use 'auf den' or fuse it: 'der Film, auf den ich mich freue'.
✅ Der Film, auf den ich mich freue.
The film I'm looking forward to.
Using a preposition + 'was' for things instead of a wo-compound.
❌ Über was sprecht ihr?
Substandard — for a thing, German fuses this into 'Worüber sprecht ihr?'.
✅ Worüber sprecht ihr?
What are you talking about?
Forgetting the linking -r- before a vowel.
❌ Woauf wartest du?
Incorrect spelling — 'auf' begins with a vowel, so the form is 'Worauf' with a linking -r-.
✅ Worauf wartest du?
What are you waiting for?
Using a wo-/da-compound for a person. Compounds are for things; people get a real pronoun.
❌ Worauf wartest du? — Auf meine Schwester.
Incorrect — since you're waiting for a person, the question needs 'Auf wen', not the thing-compound 'worauf'.
✅ Auf wen wartest du? — Auf meine Schwester.
Who are you waiting for? — For my sister.
Key Takeaways
- German never strands a preposition at the end of a clause.
- For people, the preposition is pied-piped to the front with its pronoun: Mit wem?, der Mann, für den ich arbeite.
- For things, the preposition fuses with wo- (questions) or da- (statements) into one word: worüber, womit, darauf, daran.
- A linking -r- appears before vowel-initial prepositions: worauf, worüber, woran, darauf.
- "The thing I'm waiting for" → auf das ich warte or worauf ich warte — but never ... das ich warte auf.
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Start learning German→Related Topics
- wo-Compounds: wofür, womit, woraufB1 — How German asks 'what for / with what / on what' about a thing by fusing wo(r)- with a preposition, why people keep auf wen, and why German has no preposition stranding.
- Relative Clauses with PrepositionsB2 — German never strands a preposition: it pied-pipes to the front of the relative clause, sets the case of the pronoun, and for thing-antecedents fuses into a wo-compound.
- Verbs with Fixed PrepositionsB1 — The large class of German verbs that govern a fixed preposition with a fixed case (warten auf + Akk., teilnehmen an + Dat.) — why the preposition is never the literal English one and the two-way case is lexically frozen.
- da- and wo-Compounds with Prepositional VerbsB2 — How prepositional verbs build da-compounds for things and wo-compounds in questions, while keeping preposition plus pronoun for people.
- wo, wohin, woher (Location vs Direction)A2 — German splits English 'where' into three question words — wo (location), wohin (direction to), woher (origin) — and the choice is tied directly to case and the aus/nach system.
- da-Compounds: dafür, damit, daraufB1 — How German fuses da(r)- with a preposition to refer back to a thing, why animacy decides between damit and mit ihm, and how to insert the linking -r-.