What am I riddles

what am Itricky

While I am in air, I am not in oxygen. I am also in water, but not in hydrogen. I am necessary in all animals, but you won't find me in the zoo. Look in all brains and you'll find me there too. What am I?
The Letter A.
66.53 %
200 votes
cleanwhat am I

We can be boring, Or interesting. We can be long, Or short. We can have pictures, Or just words. Many love us, But many also hate us. What are we?
Books.
66.15 %
113 votes