When one verb introduces another verb's action — "I try to come earlier," "it's important to be on time" — German links them with zu + the infinitive, parked at the end of the clause: Ich versuche, früher zu kommen. This looks like English "to + verb," but two things differ sharply: German pushes the zu-infinitive to the very end, and a key group of verbs (modals and perception verbs) take a bare infinitive with no zu at all.
The basic pattern
A zu-infinitive clause has the structure: [main clause], [the rest of the clause] + zu + infinitive. The infinitive sits last; zu immediately precedes it.
Ich versuche, früher zu kommen.
I'm trying to come earlier. — 'zu kommen' at the end of the clause.
Sie hat vergessen, das Licht auszumachen.
She forgot to turn off the light. (everyday)
Wir hoffen, euch bald wiederzusehen.
We hope to see you again soon.
Compare the English and German order: English keeps "to come" right after "try"; German moves the whole infinitive phrase to the back, with everything else stacked in between.
Three things that govern a zu-infinitive
A zu-infinitive can be triggered by a verb, an adjective (after sein), or a noun.
After certain verbs — versuchen, hoffen, vergessen, beginnen, anfangen, aufhören, sich freuen, vorhaben, beschließen, and many more:
Es hat angefangen zu regnen.
It has started to rain. (everyday)
Ich freue mich, dich endlich kennenzulernen.
I'm glad to finally meet you.
After sein + adjective — wichtig, schön, schwer, leicht, möglich, gesund, verboten:
Es ist wichtig, pünktlich zu sein.
It's important to be on time.
Es ist nicht leicht, eine neue Sprache zu lernen.
It's not easy to learn a new language.
After certain nouns — especially Zeit, Lust, Möglichkeit, Gelegenheit, Angst, Recht:
Ich habe keine Zeit, das jetzt zu machen.
I don't have time to do that right now. (everyday)
Hast du Lust, heute Abend ins Kino zu gehen?
Do you feel like going to the cinema tonight? (informal)
The big rule: modals and perception verbs take a BARE infinitive
Here is the distinction that decides everything: a small but extremely frequent group of verbs takes the infinitive without zu. These are the modals (können, müssen, wollen, sollen, dürfen, mögen), the verb lassen, and the perception verbs sehen and hören (and often fühlen, spüren).
| Governing verb | Infinitive form | Example |
|---|---|---|
| modals (müssen, können...) | bare infinitive (no zu) | Ich muss gehen. |
| lassen | bare infinitive (no zu) | Ich lasse das Auto reparieren. |
| sehen / hören | bare infinitive (no zu) | Ich höre ihn singen. |
| almost everything else | zu + infinitive | Ich versuche zu gehen. |
Ich muss jetzt gehen.
I have to go now. — modal: bare infinitive, NO zu.
Ich höre die Kinder draußen spielen.
I hear the children playing outside. — perception verb: bare infinitive.
So the zu/no-zu choice hinges entirely on which verb is doing the governing. If it's a modal, lassen, or a perception verb → bare infinitive. Otherwise → zu. There is no logic to memorize beyond this small closed list; everything else takes zu.
Where zu goes inside a separable verb
This catches everyone out. With a separable verb (like aufstehen, einkaufen, anrufen, ausmachen), the zu slots between the prefix and the stem, and the whole thing is written as one word: aufzustehen, einzukaufen, anzurufen, auszumachen.
| Separable verb | zu-infinitive |
|---|---|
| aufstehen | aufzustehen |
| einkaufen | einzukaufen |
| anrufen | anzurufen |
| vorbeikommen | vorbeizukommen |
Es ist schwer, jeden Tag früh aufzustehen.
It's hard to get up early every day. — zu sits inside: auf-zu-stehen.
Vergiss nicht, sie morgen anzurufen.
Don't forget to call her tomorrow.
Inseparable verbs (verstehen, bezahlen, erklären) keep zu in front as normal: zu verstehen, zu bezahlen, zu erklären — because their prefixes never split off.
The comma
A zu-infinitive clause is normally set off by a comma, especially when it has its own objects or modifiers, or follows a correlate like es, Zeit, Lust. Under the current rules a comma is mandatory when the clause is introduced by um/ohne/(an)statt (covered on the next page) or depends on a correlate; in other simple cases it is optional but customary.
Ich habe beschlossen, ab Montag mehr Sport zu machen.
I've decided to do more sport starting Monday. — comma before the zu-clause.
Es macht Spaß, mit dir zu kochen.
It's fun to cook with you. — correlate 'es' triggers the comma. (informal)
Common Mistakes
❌ Ich versuche kommen früher.
Incorrect — 'versuchen' requires 'zu', and the infinitive goes to the end.
✅ Ich versuche, früher zu kommen.
I'm trying to come earlier.
❌ Ich muss zu gehen.
Incorrect — modals take a BARE infinitive; no 'zu'.
✅ Ich muss gehen.
I have to go.
❌ Vergiss nicht, sie zu anrufen.
Incorrect — with separable verbs 'zu' goes inside, between prefix and stem.
✅ Vergiss nicht, sie anzurufen.
Don't forget to call her.
❌ Ich höre ihn zu singen.
Incorrect — perception verbs (sehen/hören) take a bare infinitive.
✅ Ich höre ihn singen.
I hear him singing.
❌ Es ist wichtig pünktlich sein.
Incorrect — after 'sein + adjective' you need 'zu' + infinitive (and a comma).
✅ Es ist wichtig, pünktlich zu sein.
It's important to be on time.
Key Takeaways
- Most verbs, adjectives (after sein), and certain nouns trigger zu + infinitive at the end of the clause.
- Modals, lassen, and perception verbs (sehen/hören) take a bare infinitive — no zu.
- With separable verbs, zu goes inside: aufzustehen, anzurufen — written as one word.
- The zu-infinitive clause is usually set off by a comma.
- The whole zu/no-zu decision depends on which verb governs the infinitive.
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Start learning German→Related Topics
- 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.
- 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.
- Separable Verbs with zu, Modals, and in Subordinate ClausesB1 — The three contexts where separable verbs do not split: with zu (nesting it inside), after a modal, and in verb-final subordinate clauses.
- Infinitive Clauses (zu-clauses)B1 — A zu-clause is a compressed subordinate clause with no subject of its own — it borrows the main clause's subject, ends in zu plus the infinitive, and is the reason German cannot say 'I want you to come' with an infinitive.
- Modal Verbs: OverviewA2 — The six German modal verbs, their shared word order, and the irregular present tense that makes ich and er identical.