移民通常被定义为“永久或半永久的居住变化”。

Migration is usually defined as "permanent or semipermanent change of residence".

youdao

我们永远也不会知道这种计算能力是何时、如何发展起来的，但可以肯定的是，在人类形成半永久定居点的时候，这种计数法已经发展得很好了。

It will never be known how and when this numeration ability developed, but it is certain that numeration was well developed by the time humans had formed even semi-permanent settlements.

youdao

但是到处人们都在死于胃溃疡，或者将他们的胃整个或一半切除；在我们的周围，永久性的切除术和死亡一直都在发生。

But people died from ulcers all over the place and were having their stomachs or half their stomachs removed; there were permanent, mutilating operations and deaths going on around us.

youdao