Immortality——No longer just a fantasy?

It's highly unlikely that a human could live forever. Even though the average human life expectancy has increased dramatically since the beginning of the 20th century, it won't continue to double and triple until we're living for hundreds of years. Some scientists believe that there is a hard-coded maximum life expectancy for humans, and it's probably somewhere around 125 years old. One theory, known as the Hayflick Limit Theory, suggests that the cells in the human body may only divide and copy themselves a fixed number of times, and this limit puts arestriction on how long a person can survive. Once cells cease reproducing, organs and tissues become ineffective and shut down.

On the other hand, biological immortality is not necessarily impossible. One species of jellyfish, for example, known as the Turritopsis nutricula, seems to have the ability live forever by reversing its own aging process after sexual maturity. This type of discovery may provide comfort to futurists who hold out hope that human immortality is right around the corner. Scientists are hard at work developing pills and treatments that might add a few years to our life, but their search is hindered by how long human beings already live. It's difficult, after all, to construct a scientific experiment or clinicaltrial that may last for more than a hundred years.

小注1：表示人的寿命可以有三种说法，一种是life expectancy，一种是longevity，还有一种是life span。第一种最为通用，第二种偏学术，第三种显然最容易记忆容易书写，可根据情况选择。
例：But the increase in obesity has had a disproportionate impact on Americans' health and longevity.肥胖人群的增加对美国人的平均健康和寿命产生冲击。

小注2：around the corner，字面意思是“拐过角就到”，实际意思是“非常近了”“快到来了”，可以指时间也可以指距离。
例：The christmas is around the corner.圣诞将至。

There is also the possibility that human consciousness can achieve immortality in a non-physical form. Most religions include some form of the belief that humans were created as immortals in the first place. The Bible's tale of the fall of Adam and Eve is a classic example. After they ate the forbidden fruit from the Garden of Eden, God punished them by making them mortaland able to experience physical death.

However, most Christians believe that a conscious and immortal soul survives the death of the body.

In some religions, humans were created as mortals and then tried to achieve immortality. In Mesopotamian literature, Gilgamesh, the son of a human king and a goddess, was haunted by the thought of his own mortality after his best friend Enkidu died. A human named Utnapishtim, who had been made immortal by the gods, promised Gilgamesh immortality if he could stay awake for an entire week. Gilgamesh fell asleep, and Utnapishtim gave him a rejuvenating plant, but the plant was ultimatelyeaten by a snake, ending Gilgamesh's chance of immortality. 

小注3：in the first place，这里并不是“第一”“第一个”的意思，而是“起初”，“一开始”的意思。
例：I shouldn't have lied to you in the first place.一开始我就不该对你撒谎。

小注4：haunt，这个词字面意思和实际运用差别比较大，中文中没有对应的词，意思比较接近于中文中的“……缠身”，但一般是用在抽象的东西上，如观念，罪恶感等。
例：Jesse You've got choices, jesse. But if you make the wrong ones, It'll haunt you for the rest of your life.你还有选择的余地。但是如果你做了错误的选择，会让你剩下的一生都痛苦不堪的。