deren

Deren is a German relative pronoun used in the genitive case to indicate possession, roughly translating to English "whose" or "of whom/of which." It specifically refers to feminine singular antecedents and to all plural antecedents. For masculine or neuter singular antecedents, the corresponding genitive relative pronoun is dessen. This distinction helps form relative clauses that express ownership without repeating the possessed noun.

In usage, deren introduces a clause that describes something belonging to the antecedent. The possessed noun within the relative clause is not declined by the genitive; instead, dessen or deren marks the owner. For example: Die Frau, deren Auto rot ist, kommt später. (The woman whose car is red is coming later.) Die Kinder, deren Eltern Lehrer sind, feiern heute Abend. (The children whose parents are teachers are celebrating tonight.)

Deren is standard in formal and written German and is widely accepted for feminine singular and for plural antecedents. For masculine or neuter singular antecedents, sentences typically use dessen: Der Mann, dessen Auto neu ist, hat es verkauft. In everyday speech, some speakers may substitute and say "dessen Auto" in places where "deren" would be preferred by prescriptive grammar, but the normative rule remains: dessen for masculine/neuter singular, deren for feminine singular and for all plural antecedents.

Summary: Deren is the genitive relative pronoun in German used to express possession with feminine singular or plural antecedents, while dessen is used for masculine or neuter singular antecedents. Its primary function is to introduce a clause describing what belongs to the antecedent.