Answer:
I am full of holes but still hold water. What am I?
Open me, and you can't see me without a mirror. Close me and you can't see me at all. What am I?
It's red liquid but not liquid and it's not red. What is it?
I am the noblest musical instrument
Brown I am and much admired; many horses have I tried; tire a horse and worry a man; tell me this riddle if you can.
What made Cyclops quit teaching?