A possessive form of a noun is used to show ownership. A possessive noun is a noun that names who or what has something. Add an apostrophe and s ('s) to form the possessive of most singular nouns. Add an apostrophe (') to form the possessive of plural nouns that end with s. Add an apostrophe and s ('s) to form the possessive of plural nouns that do not end with s. For more information, visit
. http://grammar.ccc.commnet.edu/grammar/possessives.htm