These are some fun and hard riddles! Step right up, And test your mind! What comes once in a minute, twice in a moment, but never in a thousand years? 2. what disapears as soon as you say its name? 3. I belong to you, But you rarely use me, Im commonly used by others around you, what am i? 4. I have keys, but no locks i have space, but no rooms. More @Wikipedia
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