To show possession using an apostrophe, add ’s for individuals (“Smith’s car”) and just the apostrophe after the s for plurals (“the Smiths’ car,” “the Martinezes’ dog”). By convention, names from classical mythology and the Bible ending in s show possession with the apostrophe only (“Jesus’ teachings”).

Apostrophes With Two Names If you are using the names of two different people in a possessive form, you add the apostrophe and the “s” only to the second name -- “Mary and Sally’s red blouses.” If you use one person’s name and a pronoun for the other person, add the apostrophe and “s” only to the name -- “Jimmy’s and her favorite movies.

To make two nouns show separate possession, add an apostrophe and an "s" after each possessive noun. Ex: Kari's and Lynn's bikes are in excellent condition. (They each have a bike.) To make two nouns show joint possession, add an apostrophe only to the second unit.