It seems a lot of people are confused about the difference between singular and plural possessives—and wonder where the heck the apostrophe is supposed to go. Is it Phyllis’s car, or Phyllis’ car?
The general rule is simper than you might think.
If it’s singular, it’s apostrophe s:
Critics agree that the highlight of last season’s Mikado was CK’s inspired performance as Nanki-Poo.
The only answer to Morgan’s insolence, thought Courtney, is a sword-hand strike to the solar plexus.
If it’s plural ending in s, just add an apostrophe:
Rifling through her parents’ record collection, Shirlee found a mint-condition copy of Jim Nabors Sings Love Me with All Your Heart.
The contradictory nature of the witnesses’ testimonies meant that, despite those meddling kids, Linda had, in fact, gotten away with the perfect crime.
There are exceptions, of course—children’s museum, women’s restroom, for goodness’ sake, Descartes’ moral code, et al.—but if you can get the basic singular/plural thing figured out, the rest will come much more readily.
by Linda