下面是两道供习作者练习的题目，要求按这种方法去写： （一）题，就中心句提问，找出中心词，列出不少于三个方面的论据。 （二）题，找出中心词，就中心词进行题问，列出论据，写出文章。 先自己动手写，再参照后文答案并背诵范文。 （一）Good Health 1)Good Health is essential for a happy and enjoyable life. 2)The key to good health is largely up to our own efforts. 3)Therefore, as young people, we should pay much attention to our health. Reference Key 1.a)Key word: essential b)Question: Why is it essential c)Outline points: word beauty entertainment(娱乐) 2.a)Key word: key b)Question: What are the keys? c)Points: exercise(体育锻炼) nutrition(营养) optimism(心情乐观) 3.a)Key word: attention b)Question. Why should we pay attention? c)Points: country.oneself 范文：Air Pollution Air pollution is becoming a serous problem. A great deal of energy is needed to run the factories of modern industrialized nations. Automobiles, trains, planes and buses need energy, too. Nearly all of this energy is maintained by burning fuels. The burning produces wastes. Some of the wastes get into the air, causing air pollution. This burning fuel gives off carbon monoxide that is harmful to our health, Carbon monoxide is a colorless, ordorless gas, and a deadly poison. When we inhale this poisonous gas, it will irritate the lungs, causing skin illness and hurts the eyes. Most electricity is generated by steam turbines. About half of the sulfur dioxide in the air comes from burning fuel to make steam. Nuclear power is thought to be a safe way of generating power. But the radioactive materials in these plants could present a danger in an accident. It is now high time we took measures. Encouragingly, people everywhere have come to know the seriousness of air pollution. A satisfactory and complete solution to this problem requires the efforts and attention of all people. Certain streets should be closed to automobiles to lower the pollution levels. The amount of carbon monoxide that an engine gives off can be reduced by special devices. Also, engineers try to design and locate new plants that will do minimum damage to the environment.