Are you guys serious! Ok... so if you want to use you're....all you have to do is say the sentence and put "you are" in it. If it doesn't work...then it is the your. You're going with us. This is your book. (You can't say...This is you are book.) With their, there, and they're.. they're...say the sentence...if you can put "they are" in it...then use it They're going to the store. their...this is talking about something that someone owns. This is their book. (They own the book.) there....this is any old there... Go over there. I teach this to second graders...they have no problem