It’s time for a language lesson – that bugaboo of so many: the possessive s.
Let’s start with the worst offender: its. Notice that there is no apostrophe. None of the personal pronouns use the apostrophe in their possessive forms. We don’t write hi’s, her’s or our’s, so don’t write it’s for the possessive. What makes it confusing is that, unlike the other pronouns, “it’s” is a valid word. It’s the contraction of “it is” or “it has,” like the first word in this sentence. Got it? Good. It’s reassuring to know that you understand its rule.
The standard rule for nouns is even simpler. Add apostrophe S to make the possessive of a singular noun, e.g. a dog’s life. If the noun is plural ending in s, then the apostrophe goes after the S, e.g. dogs’ lives. If the plural ends in another letter, like children, treat it like the singular and add apostrophe s (Children’s Hour). Nearly everyone gets this right. Where the trouble usually begins is with nouns that end in S, especially names. Like mine. This blog is not Russ’ blog. It is Russ’s blog. That’s right. Even as I am typing this, the Firefox spellchecker is marking Russ’s as wrong and Russ’ as right, even though it should be the other way around. In short, the correct way is to treat words ending in S the same as all other words.
The only exception is for those rare words that end in two successive pronounced S sounds, like Jesus or narcissus. One easy way to think of this is to think how you pronounce the word. The possessive of Russ is pronounced differently from the singular Russ, i.e. it rhymes with trusses, not truss. You pronounce an extra S sound, so it is spelled with an extra S after the apostrophe. But the possessive of Jesus is pronounced the same as the word Jesus, i.e. in Jesus’ name we pray. So Jesus just take the apostrophe without the extra S. Take another example. Suppose you had a friend named Jones. If you wanted to visit him you might say “Let’s go to Jones’s house.” You wouldn’t say “Let’s go to Jones’ house” because that sounds like you’re saying “Let’s go to Joan’s house.” In other words, you pronounce the possessive S, so it takes the apostrophe S. And if Jones had a family, you might say, “I see the Joneses.” There is no possessive and no S; it’s just the plural. But if you visited them, you might say I went to the Joneses’ house.” Notice that you pronounce the plural possessive the same way you pronounce the simple plural. So you just add on the apostrophe without another S. In short, if you pronounce the plural with an extra S sound, you must add the extra S after the apostrophe. If not, no.