Time
时间
If you can read a clock, you can know the time of day.
如果你会看表,那你就能够知道一天当中的时间。
But no one knows what time itself is.
但没人知道时间是什么。
For all our success in measuring the smallest parts of time, time remains one of the great mysteries of the universe.
虽然人类能够对时间进行精确的测量,但时间仍然是宇宙最大的奥秘之一。
One way to think about time is to imagine a world without time.
思考时间的一种时间是想象没有时间存在的世界。
There could be no movement,
那就没有运动,
because time and movement cannot be separated.
因为时间和运动密不可分。
A world without time could exist only as long as there were no changes, for time and change are linked.
没有时间存在的世界,就没有变化,因为时间与变化是相互关联的。
We know that time has passed when something changes.
当事情发生改变时,我们知道时间已流逝。
In the real world with time, however, changes never stop.
在现实世界中,变化永不停止。
Some changes happen only once in a while, like an eclipse of the moon.
有些变化偶尔才有一次,如月食。
Others happen repeatedly, like the rising and setting of the sun.
有些变化则重复出现,如日出日落。
Huamns always have noted natural events that repeat themselves.
人类注意到自然现象的循环反复,
When people began to count such events, they began to measure time
也就开始进行计算,进而测量时间。