If te have it, te want to share it. If te share it, te don't have it. What is it?
A secret.

The più te have of it, the less te see. What is it?
Darkness

What book was once owned da only the wealthy, but now everyone can have it?
You can't buy it in a bookstore o take it from a library.
A telephone book.

What gets whiter the dirtier that it gets?
A chalkboard

What happened in the middle of the twentieth century that will not happen again for 4,000 years?
The anno 1961 can be read upside down and that won't happen again until 6009!

What has no beginning, end, o middle?
A doughnut.

What has to be...