DD (18) calls herself the Grammar Nazi (I am so proud of her). She is very smart, writes well (at 9 she was noticed by her school).

Both of us have problems with people's use of your/you're. Your is possessive. YOUR book, YOUR toe.

YOU'RE is a contraction. The ' replaces the missing letter a. It is 2 words put together. YOU ARE, take away the A, put in the ' as you combine them = YOU'RE as in YOU'RE here. YOU'RE fine.