"My family likes her chocolate cake."
Translation:המשפחה שלי אוהבת את עוגת השוקולד שלה.
You use it before a direct object but only if the direct object is definite. E.g., "I'm taking the book; I want the cake, his cake, Sarah's cake", etc., all require את. But "I am taking a book; I want chocolate cake; I want a chocolate cake," etc., do not use את.