When one verb takes another verb's infinitive, German has to decide whether to insert the little word zu in front of it: Ich versuche *zu schlafen but *Ich will schlafen. Getting this right is mostly a matter of knowing one short list. The bare-infinitive verbs form a small, closed set; everything outside that set takes zu. So instead of memorizing hundreds of verbs, you memorize one group and apply a single default: use zu unless the governing verb is on the bare list.
The default: zu + Infinitiv
The overwhelming majority of German verbs that govern another verb attach it with zu, and the infinitive goes to the end of the clause:
Ich versuche, jeden Tag eine Stunde zu lesen.
I try to read for an hour every day.
Sie hofft, bald eine neue Wohnung zu finden.
She hopes to find a new flat soon.
Wir haben vor, im Sommer nach Italien zu fahren.
We're planning to drive to Italy in the summer.
Common zu-takers include versuchen, hoffen, vergessen, beginnen, anfangen, aufhören, sich freuen, scheinen, vorhaben, beschließen, sich entscheiden, planen, vermeiden, wagen, vorschlagen — and hundreds more. If a verb is not in the bare list below, assume it takes zu.
The bare-infinitive list (no zu)
Only a handful of verb groups take the infinitive without zu. They are easy to remember as four categories:
| Group | Verbs | Example |
|---|---|---|
| Modal verbs | können, müssen, dürfen, sollen, wollen, mögen | Ich muss gehen. |
| werden (future) | werden | Ich werde anrufen. |
| Perception verbs | sehen, hören, fühlen, spüren | Ich höre ihn singen. |
| lassen | lassen | Ich lasse das reparieren. |
| Motion / staying | gehen, fahren, kommen, bleiben | Ich gehe schwimmen. |
A few verbs — lernen, lehren, helfen — sit on the fence: they take a bare infinitive when the construction is short, but zu once the infinitive carries its own objects (Er hilft mir tragen but Er hilft mir, die Kisten in den Keller zu tragen).
Modals and werden
Du kannst ruhig später kommen.
You can come later, no problem.
Ich werde dich morgen anrufen.
I'll call you tomorrow.
Perception verbs (the AcI construction)
Perception verbs build an accusativus cum infinitivo ("accusative with infinitive"): you perceive someone doing something. The perceived person is in the accusative, and the action follows as a bare infinitive:
Ich sehe ihn kommen.
I see him coming.
Wir hörten die Kinder im Garten lachen.
We heard the children laughing in the garden.
lassen
lassen covers "let," "have something done," and "leave." All take the bare infinitive:
Ich lasse mein Auto in der Werkstatt reparieren.
I'm having my car repaired at the garage.
Lass mich das machen!
Let me do that!
Motion and bleiben
Verbs of going/coming plus an activity take a bare infinitive — the activity names the purpose of the motion:
Gehst du heute Abend tanzen?
Are you going dancing tonight?
Bleib doch noch ein bisschen sitzen.
Do stay sitting a little longer.
The diagnostic
Run the governing verb through one quick filter:
- Is it a modal (können, müssen, …) or werden? → bare.
- Is it a perception verb (sehen, hören, fühlen, spüren)? → bare (AcI).
- Is it lassen? → bare.
- Is it motion/staying (gehen, fahren, kommen, bleiben) + an activity? → bare.
- Anything else? → zu.
Four yes-or-no checks, then a default. That is the entire system.
zu with separable verbs: it goes inside
Separable-prefix verbs hide a trap. When such a verb takes zu, the zu slots between the prefix and the stem, written as a single word:
| Verb | zu-infinitive |
|---|---|
| anrufen | anzurufen |
| aufstehen | aufzustehen |
| einkaufen | einzukaufen |
| mitkommen | mitzukommen |
Ich habe vergessen, dich gestern anzurufen.
I forgot to call you yesterday.
Es ist schwer, jeden Morgen früh aufzustehen.
It's hard to get up early every morning.
Inseparable-prefix verbs (verstehen, bezahlen, erklären) keep the zu in front, as normal: zu verstehen, zu bezahlen.
Adverbial infinitive clauses: um/ohne/(an)statt … zu
Three subordinators build adverbial infinitive clauses and always require zu: um … zu (in order to), ohne … zu (without doing), (an)statt … zu (instead of doing):
Ich bin zu früh aufgestanden, um den Zug zu erwischen.
I got up too early in order to catch the train.
Er ging, ohne ein Wort zu sagen.
He left without saying a word.
These clauses work only when the subject is the same as the main clause's; otherwise you switch to a full subordinate clause (damit …).
brauchen: the half-modal
brauchen ("to need") behaves like a modal — and so takes a bare infinitive — but only in negative or restricted contexts (nur, nicht, kein). Standard German still prefers zu here, but the bare version is extremely common in speech:
Du brauchst nicht zu kommen, wenn du müde bist.
You don't need to come if you're tired.
Du brauchst nur Bescheid zu sagen.
You only need to let me know.
English contrast
English makes the same bare-vs-marked split, but the boundary sits in a different place, which causes predictable interference:
- English modals take a bare infinitive (I must go), and so do German modals — so far so good.
- But English uses to with verbs like try, hope, forget, begin (try to sleep), and German matches with zu — so this group also lines up.
- The mismatch is with perception and let: English says I see him come / I let it go (bare), and German agrees (ich sehe ihn kommen, ich lasse es gehen) — but English help and make diverge from German helfen and the causative lassen in subtle ways. The reliable move is to trust the German list, not the English one.
Common Mistakes
❌ Ich muss zu gehen.
Wrong — modals take a bare infinitive; no zu after muss.
✅ Ich muss gehen.
I have to go.
❌ Ich versuche kommen.
Wrong — versuchen is not on the bare list, so it needs zu.
✅ Ich versuche zu kommen.
I'm trying to come.
❌ Ich habe vergessen, dich zu anrufen.
Wrong placement — with a separable verb the zu goes inside: anzurufen.
✅ Ich habe vergessen, dich anzurufen.
I forgot to call you.
❌ Ich werde zu kommen.
Wrong — werden as future auxiliary takes a bare infinitive.
✅ Ich werde kommen.
I'll come.
❌ Wir gehen zu schwimmen.
Wrong — motion verb plus activity is bare: schwimmen gehen.
✅ Wir gehen schwimmen.
We're going swimming.
Key Takeaways
- The bare-infinitive verbs are a closed set: modals, werden, perception verbs (sehen, hören, fühlen, spüren), lassen, and motion/staying verbs (gehen, fahren, kommen, bleiben).
- Everything else takes zu — make zu your default and only the short list takes a bare infinitive.
- With separable verbs, zu goes between prefix and stem as one word: anzurufen, aufzustehen.
- um/ohne/(an)statt … zu always require zu.
- brauchen with nur/nicht acts like a half-modal and is often bare in speech.
Now practice German
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Start learning German→Related Topics
- 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.
- The Bare Infinitive (without zu)B1 — The small set of verbs — modals, perception verbs, lassen, and motion verbs — that take a plain infinitive with no zu, and the double-infinitive Perfekt they trigger.
- lassen: let, have done, and leaveB2 — The versatile verb lassen — permissive 'let', causative 'have something done', the reflexive sich lassen passive, and standalone 'leave/stop' — plus its double-infinitive Perfekt.
- um...zu, ohne...zu, (an)statt...zuB1 — The three infinitive conjunctions for purpose, 'without doing', and 'instead of doing' — and the same-subject rule that forces damit when subjects differ.
- Modal Verbs: OverviewA2 — The six German modal verbs, their shared word order, and the irregular present tense that makes ich and er identical.
- Verbs of Perception and CausationB2 — How sehen, hören, fühlen, spüren and causative lassen take a bare infinitive with an accusative subject, and why their Perfekt uses the double-infinitive construction.