Mystery of Time

If you can read a clock, you can know the time of [day:night] . But no one knows what time itself is. We cannot see it. We cannot [touch:feel] it. We cannot hear it. We know it only by the way we mark its passing. For all our success in measuring the smallest parts of time, time remains one of the great [mysteries:invention] of the universe. One way to think about time is to imagine a world without time. There could be no [movement:wave] because time and movement cannot be [separated:divided] . A world without time could exist only as long as there were no changes. For time and change are linked. We know that time has passed when something changes.