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“The answer to this riddle has a hole in the middle,
And some have been known to fall in it.
In tennis it's nothing, but it can be received,
And sometimes a person may win it.
Though not seen or heard it may be perceived,
Like princes or bees, it's in clover.
The answer to this riddle has a hole in the middle,
And without it, one cannot start over.”
This is a riddle that comes from Trenton Lee's book, The Mysterious Benedict Society and the Prisoner's Dilemma