Infinitive with zu
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Learn when German uses an infinitive phrase with zu, how it is formed, and when modal verbs take an infinitive without zu. Practise separable verbs and replacing a dass-clause when both clauses share the same subject.
Explanation
The infinitive with zu
An infinitive phrase complements a main clause. It contains zu + infinitive and normally follows the main clause.
Mia versucht, früher zu schlafen.
When do we use zu + infinitive?
It commonly follows impersonal expressions, nouns used with haben, and verbs such as versuchen, vorhaben, versprechen, empfehlen, anfangen, aufhören, and sich freuen.
| Trigger | Example |
|---|
| impersonal expression | Es ist sinnvoll, eine Pause zu machen. |
| noun with haben | Wir haben die Absicht, im Mai umzuziehen. |
| certain verb | Leo verspricht, pünktlich anzurufen. |
Word order and separable verbs
The infinitive phrase follows the main clause, and the infinitive is last:
Jana hat keine Zeit, heute lange zu kochen.
With a separable verb, zu goes between the prefix and the verb stem: anzurufen, einzukaufen, mitzubringen.
When is there no zu?
Modal verbs such as können, müssen, dürfen, sollen, wollen, and möchten take a second infinitive without zu:
Wir müssen jetzt gehen. Sam will morgen länger bleiben.
An infinitive without zu is also common after perception verbs such as sehen and hören, and after lassen.
Replacing a dass-clause
If the understood subject is the same in both parts, an infinitive phrase can replace a dass-clause:
Nora verspricht, dass sie die Tür abschließt. Nora verspricht, die Tür abzuschließen.
If the subjects differ, the replacement is not possible: Nora hofft, dass Paul die Tür abschließt. (Nora hopes that Paul locks the door.)
Comma
A comma is required, among other cases, when the infinitive phrase depends on a noun such as Absicht or Wunsch, or begins with um, ohne, statt/anstatt, außer, or als. In other contexts it can be optional. This lesson uses it consistently for clarity.
Exercises
- Sort each construction: infinitive **with zu** or infinitive **without zu**. (5)
- Replace the **dass**-clause with an infinitive phrase using **zu**. Write the complete sentence. (10)
- Put the words in the correct order. Mind the comma and the position of **zu** in separable verbs. (10)
A2 · German · Grammar