Should I use apostrophe-s(
's) or only a apostrophe(
') with the noun to show possession when the noun is singular but it ends with s.
This is a largely debated topic in the grammar world. I do need to admit, I have a definite bias toward using s's, but I'm slowly losing the battle with the world. Here are the arguments:
s's: technically correct grammar; is clear on the singularity of the noun
s': now accepted grammar; less clutter; theoretically easier for the reader
Excerpt from The Guide to Grammar and Writing:
Some writers will say that the -s after Charles' is not necessary and that adding only the apostrophe (Charles' car) will suffice to show possession. Consistency is the key here: if you choose not to add the -s after a noun that already ends in s, do so consistently throughout your text. William Strunk's Elements of Style recommends adding the 's. (In fact, oddly enough, it's Rule Number One in Strunk's "Elementary Rules of Usage.") You will find that some nouns, especially proper nouns, especially when there are other -s and -z sounds involved, turn into clumsy beasts when you add another s: "That's old Mrs. Chambers's estate." In that case, you're better off with "Mrs. Chambers' estate."
To further iterate my bias, I added the bold in the text myself, as Strunk's style guide is very highly held in the writing community. :)