We live in a time when,more than ever before in history,people are moving about.

We live in a time when,more than ever before in history,people are moving about.
We live in a time when,more than ever before in history,people are moving about.

We live in a time when,more than ever before in history,people are moving about.
时间是主语
更合适的翻译该是
我们生活在一个人们流动空前的时代.

我们生活在这样的一个时代，人们的流动性在历史上是空前的。

我们生活在这样一个时代,人们到处流动,甚于史上任何时期.