题目

根据要求填空： （1） 酸雨给人类生活和社会发展带来了严重危害．汽车尾气是导致酸雨的重要原因，为减少有害气体的排放，人们在汽车排气管上安装“催化转化器”，使尾气中的一氧化碳和一氧化氮转化为空气中体积分数最多的气体（填化学式）和CO2 ． （2） 化学反应中，元素的化合价升高，则该元素所在的反应物是还原剂，反之则为氧化剂．那么上述反应中的NO是剂． （3） 上述反应产生的CO2大量排放会导致，植树造林、低碳 阅读理解。      Not only adults but also teenagers have problems in their life. Here is a survey showing the main problems of teenagers.      They feel stressed because they have too much homework to do both at school and at home. They have lots of exams to take. And parents usually send them to different classes at weekends. They don't have their own time to do what they are interested in. Now more and more teenagers are getting short-sighted (近视). They often read in bed or keep reading for a long time without having a rest. Some of them are crazy about playing computer games. Some spend too much time watching TV Another serious problem among teenagers is that many of them are becoming fat. They eat too much junk food, but they take little exercise.      I think teenagers should think of ways to deal with the problems. They should make a plan for study and hobbies and find time to relax as much as possible.                                                            Information Card How many problems are mentioned in the survey? 1._________ Why do teenagers feel stressed? 2. Because they have too much _________. What makes teenagers become fat? 3. Too much _________ and too little exercise. What problem is caused by computer games? 4. Playing computer games too much will make     teenagers _________. How can teenagers relax themselves? 5. By _________ a plan for study and hobbies.