<Dt> Possessive pronouns and adjectives </Dt> <P> No apostrophe is used in the following possessive pronouns and adjectives: yours, his, hers, ours, its, theirs, and whose . </P> <P> The possessive of it was originally it's, and many people continue to write it this way, though the apostrophe was dropped in the early 1800s and authorities are now unanimous that it's can be only a contraction of it is or it has . For example, U.S. President Thomas Jefferson used it's as a possessive in his instructions dated 20 June 1803 to Lewis for his preparations for his great expedition . </P> <P> All other possessive pronouns ending in s do take an apostrophe: one's; everyone's; somebody's, nobody else's, etc . With plural forms, the apostrophe follows the s, as with nouns: the others' husbands (but compare They all looked at each other's husbands, in which both each and other are singular). </P>

What is the mark in a contraction called