I found this one in a book. I'm not sure if it's 100% correct, but it's something along the lines of this:Tall I am young.
Short I am old.
With light I do glow.
Breath is my foe.
The book is one of the Inheritance Cycle, I think Eldest (the second one) but I'm not positive. They are really good books, you should read them!
OMG I THOUGHT I HAD ALREADY PUBLISHED THIS PART I AM A DUCKING FAILURE!!!!! Sorry . . .
But anyways, there you go. Three comments and I'll post the answer! See ya!