<p>I think this is one of those usages that has become a matter of style and choice. If your teacher assigns Strunk & White as the arbiter of rules for your papers, then follow those rules. If the teacher prefers MLA rules, they may be different (don’t know!), but follow them for those papers. In your personal corrspondance, use what you like! – they are both accepted. If you’re doing work for publication, like books or magazines, the copy editors will punctuate according the house style manual.</p>
<p>Not an English teacher, but I play one on TV :)</p>
<p>The yyys’ form is used when the word is both plural and possessive. As in: “The touchdown capped the Bruins’ final scoring drive.” Bruin, in this sentence, is both plural and possessive. </p>
<p>The yyys’s form is correct when the word ends in an s but is not actually plural – possessive only. Charles and Burns fall into that category –>end in s but are not inherently plural.</p>
<p>Both versions are considered correct, but the yyys’ version a more modern usage. Strunk & White are classic, but that’s another word for old. </p>
<p>I prefer yyys’s because I honor Strunk, but as suggested above if someone you’re writing for or if you prefer something different, follow it.</p>
<p>BTW, this is one of the least important things Strunk has to say. For instance, I think what he says about vigorus writing matters more, even if I haven’t internalized it as much as I should. :D</p>
<p>The Chicago Manual of Style is somewhat faithful to Strunk and White (uses Strauss’s and so forth for most names ending in “s”) but calls for some exceptions, notably a multisyllable name ending, and I quote, in an “eez” sound–hence Xerxes’ and so on. The Chicago Manual is heavily used by many publishers and some academics. I would concur with other posters that for schoolwork you pretty much have to use the style book your instructor recommends, and for paid work you abide by the style of your employer. There is no single correct style, though my own preference is almost always for Chicago.</p>
<p>The rule, as I’ve heard it, is that if you pronounce the extra syllable, e.g., Strauss’s (Strauss-ez), you add the “s” after the apostrophe. If no extra syllable is pronounced, e.g., attorneys’ fees, you don’t add the “s.”</p>
<p>Mice’s race, men’s secrets, children’s toys, but Jesus’ followers. </p>
<p>It looks like the rule shown by Coureur does not apply to plurals that do not end in “s”, and to ancient names ending in z or s. The sound of the following word also seem to influence the possessive form as in conscience’ sake. </p>
<p>I go with S & W.
Otherwise how would you know when you write Burns’ that you are talking about a person with the last name of Burns, as opposed to two people named Burn?</p>
<p>However, NY Times style book says "If the word ends in a sibilant sounds (ch, j, s, sh or z) separated only by a vowel sound, drop the s after the apostrophe (Kansas’ climate, the sizes’ range) But keep the s after the apostrophe when a name ends in a silent sibilant letter (Arkansas’s ; Malraux’s)</p>
<p>Ha Ha… Not sure I have a clue what that means…</p>
<p>When the possessive of Arkansas is pronounced, I don’t think it’s “Ar-kan-saws-es” but “Ar-kan-saws,” so you’d go with Arkansas’ without the extra “s.”</p>