Grammar Help — Words — Possessive

An apostrophe before the s is used to indicate possessive case	Frank's dog. Frank's dog's bone. Exceptions: It's = it is so use "its" for possessive. Example: It's Frank's dog. Frank's dog chews its bone.
An apostrophe is used after the s only when the noun ends in s and the addition of another s is awkward.	Example: The Smith's house is beside the Jones' house Example: It's the Raiders' ball on the 10 yard line! Example: I took a big bite out of the octopus' tentacle and he didn't like it! Note: An apostrophe is never used after the s in its.