In the past it was not uncommon for a man to die at forty, having lived a full life. But now we consider a lifespan of forty years to be very short. It is not unusual for people to live into their eighties and nineties, and some even reach 100. What’s more, people are living long, healthy lives and are active well into their “golden years”.

Mankind’s longevity is due mainly to advances in science and technology. Medical breakthroughs have eradicated many fatal diseases that were once common. Perhaps more importantly, better general health means that people are less likely to contract infections in the first place. Better health also helps people prevent slowly debilitating conditions, such as heart disease, which can take their lives at an early age. And as civilization has advanced, our living environment and sources of food have become more sanitary. Furthermore, work is now safer and not as taxing on the human body. We do not wear out after just a few years of very hard work.

There are many reasons why people are now living longer than ever before. But what is more important is that they are living better as they live longer. It is my opinion that we have scientific and technological development to thank for this progress.

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活得更久

以前的人活到40岁就过完一生而死亡是很平常的。但是现在，我们认为40岁的寿命很短。人们活到八十几岁、九十几岁，有些甚至到100岁，是很平常的。而且，人们还能活得久而且又健康，精力充沛地迈入他们的“黄金时代”（退休期）。

人类会长寿主要是因为科学及科技的进步。医学上的重大突破已经根除了以前十分普遍的致命疾病。而更重要的也许是，大众健康的改善首先意味着人们不大可能得传染病。人们变得更健康也有助于预防罹患一些会使身体状况日益衰弱的疾病，例如心脏病。这些疾病常会夺走年轻的生命。又因为文明的进步，我们的生活环境以及食物来源已经变得比较卫生。此外，现在的工作比较安全，且对人体而言没有那么繁重。我们不会因为只辛苦工作几年就变得疲惫不堪。

现代人比以前长寿的原因有很多，但更重要的是，人们活得更久，而且也活得更好。我的看法是，我们进提那的进步得益于科学和科技的发展。