Most people can, without thinking, form a possessive noun. You build one by adding an apostrophe and an “s” to a noun, as in “Occam’s razor” and “the cat’s meow.”

But things are different with pronouns. (Pronouns are those little words that stand in for nouns, such as he, she, it, they, us, him, her, you.) You NEVER use an apostrophe for the possessive form of a pronoun.

That bears repeating: You NEVER use an apostrophe for the possessive form of a pronoun. Instead, you use a different word. So the possessive of “me” is “mine” and the possessive of “he” is “his.” So far so good.

“It” is the problem pronoun. To form the possessive, “it” DOES get an “s” on the end, but it doesn’t get an apostrophe. Repeat after me: You NEVER use an apostrophe for the possessive form of a pronoun.
Here’s how to get it right for “its” and “it’s”:
• “Its” is possessive, as in “This web app is pretty, but I’m not sure about its usefulness.”
• “It’s” is a contraction of “it is,” as in “It’s time for mojitos.”

It’s confusing, I know, so any time you type an apostrophe, I recommend that you pause and remember that rule. I don’t need to repeat it again, do I?

What else trips you up when you’re writing? Let me know and I’ll try to shed some light.