Through glassy eyes, I help you see, Beneath blue waves or at high speed. A shield for eyes, my purpose clear, A trusty guard for your vision dear.

I can contain many things. Water. Wine. A message. Even a boat.

At one time a classroom must often replaced because of dust. Also slang among sports betters for the team or athlete favored to do better.

I sit and I fold, the future foretold, all within my own body. these special readings, speak volumes from silence, and map out of ridges of your body. while I think it's nonsense, these lines making sense, as too much work can have a major impact. so what readings, am I speaking about, which involve a four letter body part.

I allow passage I decide tone I am important And help you find home I'm sometimes a major And sometimes antipode Im the song singer And writer of codes What am I?