What does it mean to have a double life . Explain how calpurnia led a double life ?

A double life means living a certain way for one part of your life while living a different way for another. Calpurnia leads a double life. With the Finch kids, she speaks proper English and articulates her ideas in an educated way. At her church she speaks in the vernacular common to Negro's. Calpurnia doesn't want to upset the balance she lives between the two worlds.