Topic：Why do people live longer?
In general, people are living longer now. Discuss the causes of this phenomenon. Use specific reasons and details to develop your essay.
经济稳定、社会稳定。极端的例子：前苏联(the previous Soviet Union)解体(disintegration/breakup)后，俄罗斯的平均年龄大幅度下降
With the development of human society, people are living longer now.Many factors interact together to enable a longer life. There are three most important causes: the quality of food has been greatly improved; people could have access to medical services; more and more people realize that regular sports benefit their health.
The improving quality of our food is the most important factor of the longer life. We could have not only enough food as we want, but also more healthier food. When we preparing food, we no longer consider the cost, but pay more attention to the nutritious value of the food. With the development of transportation systems, inland people now could also enjoy seafood and tropical fruit（热带水果）.
Furthermore, governments are paying more and more money on medical establishments. Citizens could have access to medical services more easily. Because of the convenient medical service, more illnesses could be detected at an earlier stage. Also, many illnesses that had been considered fatal（致命的）could be cured（治愈）today. The better detection and cure enable people's longer life.
Last but not least, people care more for their own health. Every morning you could see people doing sports outside. More and more people have realized the saying “life is in motion."（好用的俗语，生命在于运动）Regular sports build up a strong body. Naturally, people with stronger body could resist more diseases.
To sum up, the development of our society ensures that people have longer life. People now enjoy better food and better medical services, and they spend more time on sports and exercises to build up stronger bodies. As we could predict, people are going to live even longer in the future.