• Use apostrophes to indicate possession. When you want to indicate possession with a singular noun, whether it ends in an "s" or not, you add an apostrophe and an "s" on the end. For example: "the midget's pathos," "the pathos's source" and "the source's nature." The only exception to this is the word "it," with which you indicate possession by adding an "s" alone (i.e., "its"), because the word "it's" is a contraction meaning "it is." When you want to indicate possession with a plural noun which ends in any letter other than "s," you add an apostrophe and an "s" on the end. For example: "the people's champion," "the hippopotami's excrement," and "the geese's habitat." When you want to indicate possession with a plural noun which ends in "s," you add an apostrophe on the end. For example: "the peoples' champions," "the debutantes' routine," and "the undergarments' impenetrability." That's all there is to say about indicating possession with apostrophes.

  • Use apostrophes to form contractions. Apostrophes are also used to form contractions. We are told that contractions were invented by sign-painters back in the olden days because they kept running out of room or paint when they were plying their trade. Many commentators suggest that contractions should not ever be used in writing, because they are too informal. We think that contractions are fine in informal writing or when it is necessary to convey a conversational tone, but we'll leave it up to you. The important thing is that you understand that contractions are the only other use for apostrophes. For example: "you can't so don't," "they're wrong," and "it's incorrect to use apostrophes for anything other than indicating possession or forming a contraction."

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