Ich habe vergessen, die Tür zu schließen.
English: I forgot to close the door.
In German, 'Infinitiv mit zu' means using the infinitive form of a verb together with 'zu'. It is similar to saying 'to do' something in English.
You use 'Infinitiv mit zu' in German after certain verbs, adjectives, and expressions. It is common when you want to say what someone wants, plans, tries, or needs to do.
Ich habe vergessen, die Tür zu schließen.
English: I forgot to close the door.
Sie hofft, bald nach Hause zu kommen.
English: She hopes to come home soon.
Es ist wichtig, Deutsch zu lernen.
English: It is important to learn German.
Wir versuchen, pünktlich zu sein.
English: We try to be on time.