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Possessives and Attributives
Q. Our pastor’s surname is Lentz. He is married with children, so there are several people named Lentz living in his house. When an event is scheduled to occur at his home, should we refer to it as “the Lentz’ house,” “the Lentz’s house,” or simply “the Lentz house”?
A. “The Lentz house” is fine, or “the Lentzes’ house.” The former uses an attributive, the latter a plural possessive. Although notoriously popular, your other versions are incorrect.