As the 11 of life continues to increase, we are fast losing the art of relaxation. Once you are in habit of rushing through life, being on the go from morning till night, it is hard to slow down. But relaxation is essential for a healthy mind and body.
　　Stress is a natural part of everyday life and there is no way to avoid it. In fact, it is not the bad thing it is often 12 to be. A certain amount of stress is 13 to provide motivation and give purpose to life. It is only when the stress gets out of control that it can lead to poor 14 and ill health.
　　The amount of stress a person can 15 depends very much on the individual. Some people are not afraid of stress, and such characters are 16 prime material for managerial responsibilities. Others lose heart at the first signs of 17 difficulties. When exposed to stress, in whatever form, we react both chemically and physically. In fact we make choice between "fight" or "flight" and in more primitive days the choices made the difference between life or death. The crises we meet today are unlikely to be so 18 , but however little the stress, it involves the same response. It is when such a reaction lasts long, through continued 19 to stress, that health becomes endangered. Such serious conditions as high blood pressure and heart disease have established links with stress. Since we cannot 20 stress from our lives(it would be unwise to do so even if we could) , we need to find ways to deal with it.

　　A. cancel B. pace C. extreme D. automatically
　　E. remove F. vital G. performance H. supposed
　　I. rate J. exposure K. achievement L. unusual
　　M obviously N withstand O harsh

　　答案：11. B 12. H 13. F 14. G 15. N 16. M 17. L 18. C 19. J 20. E