Answer:
Flat as a leaf round as a ring. I have two eyes but can't see a thing.
I am a word. I become longer when the third letter is removed.
What is full of holes but still holds water?
I am in the past, never in the future. I don't exist, but have existed. I saw what you saw, and this is what I will ever see. What am I?
I am the only word that looks the same when spelled upside down.
Whoever made me don't want me. Whoever bought me don't need me. Whoever use me don't know me.