Natural Life Span的意思|示意

Scientists estimate that person's natural life span is 120 years old, why?

科学家推算，人的自然寿命是120岁，为什么呢？

But 20th century medicine did little to increase the natural life span of healthy humans.

然而，20世纪的医学对健康人的自然生命周期的增长几乎无能为力。

So I tell her penguins are so old, they have outlived the dinosaurs. I tell her 1 carp has no natural life span and could technically live forever.

于是我告诉她，企鹅是很古老的动物，它们的历史比恐龙更久远。我告诉她，鲤鱼没有自然寿命，所以严格来说，它能够长生不死。

The process of aging and eventual death must finally be taken as the natural process of the life cycle, the old completing their limited life span and making way for the young.

人们必须接受衰老及最终辞世是人生周期的自然进程，老年人结束自己的寿命，为年轻人让位。

Any longer would exceed the natural life span of the potential audience and sponsors for the message conveyed: the Century of Kidney Disease Awareness?

如果时间更长的话，就会超过潜在听众与赞助者的生命周期，譬如：肾脏病省思的世纪？

But 20th century medicine did little to increase the natural life-span of healthy humans.

然而，20世纪的医学对健康人的自然生命周期的增长几乎无能为力。