What's wrong with the subject title of this post? That's right, I incorrectly used a modifier as a second-person verb-phrase.
Except that I did it on purpose as a joke to prove a point, and every day I see people making this error multiple times without knowing they're doing it. Today in fact, a co-worker made this error in emails sent to me, not once, not twice, but four times! "Your welcome Kat". ARggghhh... It took all of my willpower not to go running down the hall to her office to throttle her.
"You're" is a verb phrase that is a contraction of "you are". "Your" is a modifier adjective. Easy!
Do not use "you're" to modify nouns. "Your keys."
Do not use "your" as a second-person verb phrase. "You're up early." Here's a phrase with both: "You're moving your car, right?" In other words, you are moving the car that belongs to you.
I know I am a grammar snob. I can't help it. I also know that everyone makes mistakes like this once in awhile. I do it too! It pains me to admit it, but it's true. So I'm not about to bust out the Word Police grammar error citation cards but please people just think about what you're typing (See? Not hard at all) before you hit that send button.
See also: They're/Their