I could be whole or split in two. I never wear a jacket but I sometimes wear a shoe. I’m hard as a stone, but I’m not a bone

I rise above the ground to watch the land, sometimes I hold a clock, sometimes a bell’s command. In stories, a princess may wait inside my wall, stone and shadow standing tall.

You will find them in any store, Though a choir will have many more. Do this before you cast a line, Or else the ranger will hand you a fine. The answer did itself to itself, When found in the the book on every linguist's shelf.

I stand tall as a guardian, made of wood for my height. I helped guard old towns and forts with all of my might. Tasked to stop and slow my foe, I helped end the fight before they could show their might.

I'm wore above the the eyes using it to protect your eyes.