exercise 2:In general,people are living longer now. Discuss the cause of this phenomenon.

Among countless factors which contribute to people living longer now, three conspicuous aspects are as follows.

One of the primary causes is that the development of science and technology. Just take my hometown for example my hometown, located in the northeast of China, has a long and cold winter with the average temperature about minus 15 centigrade. Seldom can vegetables grow in this whether weather, so ancient people had to store food for winter. However, without scientific farming, it is difficult to keep a balance in nutrition, even far further from get getting enough food.

Longer living life also results from better medical skills and more effective medicine. Some mortal disease before can be cured now by operation or effective drugs. Ancient Chinese doctors did not master the skills of operation and only used herbs to treat patients that could cause death due to wrong treatment. Someone may say that modern medicine also has side effects, but scientists are trying to avoid it, and I think it will be solved one day.

Economic advance and modern concepts are responsible for longer lives as well. People now pay more attention to their health than before. It is economic advance that makes it possible to keep a balance in nutrition, to exercise to maintain a healthy body, to entertain ourselves after a heavy day.

I draw the conclusion that the development of science and technology, the improvement of medical skills and medicine, the advance of economic and modern concept, are three main contributors to longevity.

Could you please tell me what do you think are the main reasons and show some details?

Thanks!