I make up all literature, but I'm often sealed. What am I?

Answer: Letters

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I make you see the beauty of nature through colors, My name makes things weigh less And I have no weight at all. What am I?
I may be made of metal, bone, or wood and have many teeth. My bite hurts no one and the ladies love me. What am I?
I may only be given but never bought. Sinners seek me but saints do not. (one word) What am I?
I may seem real but it always turns out I was never there in the first place… you only see me during a certain resting stage. What am I?
I mean goodbye for South Americans. What am I?
I measure out time, Until in time, All is smashed into me. What am I?
I mirror your actions. What am I?
I moan, I groan, I chase after you. I never seem to rest. Time’s up for you. What am I?
I move at a tremendous speed, as fast as a car, and yet I’m always at the same place. What am I?
I move without wings, Between silken string, I leave as you find, My substance behind. What am I?
I move without wings, between silken strings. I leave as you find my substance behind. What am I?
I must be broken before you can use me. What am I?