You've learned that separable verbs crack open in a main clause and fling the prefix to the end: Ich stehe um sieben auf. But that splitting is not the verb's "natural state" — it happens only when the verb is the finite (conjugated) verb in a main clause. In three very common situations the verb stays solid, and one of them does something that surprises every learner: it nests the little word zu inside the verb. This page covers all three, because they account for most of the separable-verb errors at this level.
The governing principle
Here is the one idea that unifies everything below: a separable verb splits only when it is the finite verb of a main clause. In every other role — as an infinitive after a modal, as a zu-infinitive, or as the verb pushed to the end of a subordinate clause — it stays whole.
Context 1: After a modal — the verb stays whole at the end
When a modal verb (müssen, können, wollen…) is in charge, the separable verb appears as a plain infinitive at the end of the clause — completely unsplit.
Ich muss morgen früh aufstehen.
I have to get up early tomorrow.
Kannst du mich später anrufen?
Can you call me later?
Wir wollen heute im Markt einkaufen.
We want to shop at the market today.
The modal is now the finite verb (muss, kannst, wollen), so it takes position two and does the work. The separable verb has no conjugating to do — it sits at the end as a tidy infinitive (aufstehen, anrufen, einkaufen), written as one word. Notice this is also a Satzklammer: the modal and the infinitive bracket the sentence, just as the stem and prefix did before.
Context 2: With a zu-infinitive — zu goes INSIDE
This is the famous one. Many German verbs and constructions trigger a zu-infinitive (versuchen … zu, vergessen … zu, anfangen … zu, Lust haben … zu). For an ordinary verb, zu simply sits in front: zu kommen, zu lernen. But for a separable verb, the zu slips into the seam between the prefix and the stem, and the whole thing is written as a single word.
| Infinitive | zu-form |
|---|---|
| anrufen | anzurufen |
| einkaufen | einzukaufen |
| mitnehmen | mitzunehmen |
| aufstehen | aufzustehen |
| zurückkommen | zurückzukommen |
Ich versuche, dich morgen anzurufen.
I'll try to call you tomorrow.
Vergiss nicht, Brot einzukaufen!
Don't forget to buy bread!
Hast du Lust, heute Abend mitzukommen?
Do you feel like coming along tonight?
The logic is elegant: zu belongs grammatically between the prefix and the verb stem, so it physically goes there. An inseparable verb, having no detachable prefix, just takes zu in front as normal — zu verstehen, zu bekommen, never verzustehen.
Es ist nicht leicht, diese Regel zu verstehen.
It isn't easy to understand this rule. (inseparable verb — zu stays in front)
Context 3: Subordinate clauses — the verb rejoins at the end
In a subordinate clause (introduced by weil, dass, wenn, ob, obwohl…), German sends the finite verb to the very end. When that finite verb is separable, the prefix doesn't strand itself somewhere — the prefix and the conjugated stem reunite into one word at the end of the clause.
Watch the same verb in a main clause and then in a subordinate clause:
Ich stehe früh auf.
I get up early. (main clause — split)
Ich bin müde, weil ich früh aufstehe.
I'm tired because I get up early. (subordinate clause — rejoined at the end)
Er sagt, dass er dich heute noch anruft.
He says he'll still call you today. (subordinate — anruft rejoins at the end)
Wenn wir im Supermarkt einkaufen, nehmen wir den Bus.
When we shop at the supermarket, we take the bus. (subordinate — einkaufen written solid)
So auf + stehe fuse back into aufstehe, and an + ruft into anruft. The verb returns to looking like its dictionary self because verb-final position is, in a sense, the verb's "home."
All four environments side by side
Seeing one verb behave across all four environments — the splitting main clause plus the three non-splitting contexts — makes the pattern click:
| Context | Example with anrufen |
|---|---|
| Main clause (finite) — SPLITS | Ich rufe dich morgen an. |
| After a modal — whole infinitive | Ich will dich morgen anrufen. |
| zu-infinitive — zu inside | Ich versuche, dich anzurufen. |
| Subordinate clause — rejoins | …, weil ich dich morgen anrufe. |
English contrast
English has no equivalent of nesting a particle like zu inside a verb — "to call up" never becomes "to up-to-call." And English doesn't reunite separated particles at the end of a clause, because it never separated them onto a bracket in the first place. So both the anzurufen nesting and the verb-final weil ich … aufstehe rejoining feel alien at first. The mental shortcut: in English the particle stays put near the verb; in German the particle's behaviour depends entirely on the verb's job in the clause, and in these three jobs the safest thing it can do is stay (or get) glued back on.
Common Mistakes
❌ Ich versuche, dich morgen zu anrufen.
Incorrect — with a separable verb, zu nests inside, not in front.
✅ Ich versuche, dich morgen anzurufen.
Correct — zu goes between the prefix and the stem: an-zu-rufen, one word.
❌ Ich muss morgen früh auf stehen.
Incorrect — after a modal the infinitive is written solid, not split into two words.
✅ Ich muss morgen früh aufstehen.
Correct — the separable verb stays whole as an infinitive at the end.
❌ Ich bin müde, weil ich stehe früh auf.
Incorrect — in a subordinate clause the verb must rejoin at the very end, not split in main-clause order.
✅ Ich bin müde, weil ich früh aufstehe.
Correct — prefix and stem reunite as aufstehe at the clause end.
❌ Vergiss nicht, Brot ein zu kaufen.
Incorrect — einzukaufen is one word; zu is inserted, not written separately.
✅ Vergiss nicht, Brot einzukaufen!
Correct — written solid with zu nested inside.
❌ Es ist nicht leicht, diese Regel verzustehen.
Incorrect — verstehen is inseparable, so zu stays in front; it never nests.
✅ Es ist nicht leicht, diese Regel zu verstehen.
Correct — inseparable verbs take zu before the whole verb.
Key Takeaways
- A separable verb splits only when it is the finite verb of a main clause. Everywhere else it stays whole.
- After a modal: whole infinitive at the end (Ich muss … aufstehen).
- With a zu-infinitive: zu nests inside, written as one word (anzurufen, einzukaufen, mitzunehmen).
- In a subordinate clause: the finite verb goes to the end and the prefix rejoins the stem (…, weil ich früh aufstehe).
- Inseparable verbs never nest zu — it stays in front (zu verstehen), since they have no detachable prefix.
Now practice German
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Start learning German→Related Topics
- Separable Verbs: How They SplitA2 — How German separable verbs detach their stressed prefix and send it to the end of a main clause.
- Inseparable Prefix VerbsA2 — The eight prefixes that never split, never take ge-, and are stressed on the stem: be-, emp-, ent-, er-, ge-, miss-, ver-, zer-.
- The zu-InfinitiveB1 — When German uses zu + infinitive at the end of a clause, when it doesn't (modals and perception verbs take a bare infinitive), and where zu goes inside separable verbs.
- Modal Verbs: OverviewA2 — The six German modal verbs, their shared word order, and the irregular present tense that makes ich and er identical.
- Verb-Final Order in Subordinate ClausesB1 — Why a subordinating conjunction sends the finite verb to the very end of the clause — and why in compound tenses the auxiliary lands dead last.
- High-Frequency Separable Verbs ReferenceA2 — A practical reference of the most common German separable verbs, grouped by prefix, with meanings, participles, and the correct Perfekt auxiliary.