Kennen

Kennen is a German verb meaning to be familiar with someone or something, to have personal acquaintance or experience-based knowledge. It denotes acquaintance or familiarity and is used for people, places, and things. For facts or information, German uses wissen rather than kennen.

Kennen is a transitive verb and takes a direct object in the accusative. Examples: ich kenne ihn (I know him), ich kenne Berlin (I know Berlin), ich kenne das Buch (I know the book). In negation the object remains in the accusative: ich kenne ihn nicht.

Conjugation and forms: in the present tense the forms are ich kenne, du kennst, er kennt, wir kennen, ihr kennt, sie kennen. The simple past (Präteritum) is ich kannte, du kanntest, er kannte, wir kannten, ihr kanntet, sie kannten. The perfect is formed with haben: ich habe gekannt. When used with the related verb kennen lernen, meaning to get to know someone, the perfect form is kennengelernt: ich habe ihn kennengelernt.

Kennen lernen versus kennenlernen: both spellings are used today, but kennenlernen (one word) is the commonly preferred form for the verb meaning “to get to know someone for the first time.” The separable variant known from older usage, kennen lernen, is still understood.

Usage notes and idioms: sich auskennen means to be knowledgeable about a subject or place, and is used with reflexive pronouns: ich kenne mich in der Stadt gut aus. To know someone well can be expressed as jemanden gut kennen; an idiom is kennen wie seine Westentasche, meaning to know something or someone very well.

Kennen versus wissen: wissen covers factual knowledge or information (ich weiß, dass...), while kennen covers familiarity or acquaintance (ich kenne ihn, ich kenne Berlin). This distinction is central to correct usage in everyday German.