What does this rebus mean?

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TIME

Its something that each of us devours,
Not just us but birds, beats, trees, and flowers,
Frets iron and nibbles steel,
Toil hard stones to meal,
Exterminates king, collapse town,
And blows the mountains down.

There is an English word that can be used up to four times in a row without modifying the spelling and form a valid grammatical sentence.

Do you know what word is that?

What has many teeth, but cannot bite?

A word I know has six letters it contains, remove one letter and 12 remain. What is it?

What does this mean?

CCCCCCC

What can you serve, but never eat?

Can you count the number of quadrilaterals in the picture below?

There is a family that live in a round house. The two parents go out for a movie and leave a babysitter to watch their son. They come back and the kid was not there. Some one kidnapped him. The maid said she was cleaning in a corner. The cook said he was making pizza. The babysitter said she was getting a board game. Who kidnapped him.

There's one "sport" in which neither the spectators nor the participants know the score or the leader until the contest ends.

What is it?