Answer:
What can you throw but not catch?
I am whole but incomplete. I have no eyes, yet I see. You can see, and see right through me. My largest part is one fourth of what I once was.
Tall in the morning, short at noon, gone at night. But I'll be back soon.
My first master has four legs, my second master has two. My first I serve in life, my second I serve in death. Tough I am, yet soft beside. Against ladies cheeks I often reside.
Both punishment and sweet reward, It will befall both fool and lord. It is a spiritual scoreboard, Your every deed it does record.
People take me on walks and I run and have fun. What am I?