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：表示人的壽命可以有三種說法，一種是life expectancy，一種是longevity，還有一種是life span。第一種最爲通用，第二種偏學術，第三種顯然最容易記憶容易書寫，可根據情況選擇。
例：But the increase in obesity has had a disproportionate impact on Americans' health and longevity.肥胖人羣的增加對美國人的平均健康和壽命產生衝擊。

小注2：around the corner，字面意思是“拐過角就到”，實際意思是“非常近了”“快到來了”，可以指時間也可以指距離。
例：The christmas is around the corner.聖誕將至。

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，這裏並不是“第一”“第一個”的意思，而是“起初”，“一開始”的意思。
例：I shouldn't have lied to you in the first place.一開始我就不該對你撒謊。

小注4：haunt，這個詞字面意思和實際運用差別比較大，中文中沒有對應的詞，意思比較接近於中文中的“……纏身”，但一般是用在抽象的東西上，如觀念，罪惡感等。
例：Jesse You've got choices, jesse. But if you make the wrong ones, It'll haunt you for the rest of your life.你還有選擇的餘地。但是如果你做了錯誤的選擇，會讓你剩下的一生都痛苦不堪的。