【正文】 o do. People will continually find new ways to control pollution.5. Environmental ProtectionToday the quality of our natural environment has bee an important issue. The world population is rising so quickly that the world has bee too crowded. We are using up our natural resources and at the same time polluting our environment with dangerous chemicals. If we continue to do this, life on earth cannot survive.Concerned people have made some progress in environmental protection. Governments of many countries have established laws to protect the air, forests and sea resources and to stop environmental pollution.Still more measures should be taken to solve environmental problems. People should be further educated to recognize the importance of the problems, to use modern methods of birth control, to conserve(保存） our natural resources and recycle（再循環(huán)） our products. ?We are sure that we can have a better and cleaner place in the future.6. AutomobilesAutomobiles, as a product of modern civilization, have been playing a vital part in the daily activities of human society. Industry needs automobiles for farming as well as transportation. Every day, automobiles drive people to and from work. On weekends automobiles take families for joyful outings. And during holiday seasons, automobiles fill the highways everywhere, even in remote areas. It could be said that the wheels of automobiles move society forward.But automobiles have also given rise to a series of problems. For example, cities are overcrowded with automobiles. They create a lot of noise and traffic accidents which disable（傷殘） or kill many people each year. Worst of all perhaps is the air pollution caused by the exhaust gases produced by automobiles. Some of the gases are highly toxic(有毒的） and a serious health hazard.7. ComputerThe puter is widely used in all fields of society. Today, wherever you go, you will find puters being used. For example, puters are used in universities, large corporations, and small offices, etc. It has even entered the homes of ordinary people. As it is able to store and process a large amount of information, the puter bring about great convenience and high efficiency to people of all walks of life.Computers can help people in different ways. For example, puter help scientists in analyzing data and doing plex calculation. For another example, puters are made use of by engineers in designing a plane, or a spaceship. Besides, puters may also play a great role in helping children with their lesson. Whatever you are doing, you many find puter a useful aid.However, the puter must be designed and 包含ucted by man. What is more, it is true that puters can make decisions, but they need detailed 包含uctions and programs prepared by humans to operate. Therefore, the puter can never replace the human brain.8. TravellingIt is exciting to visit different places. As you travel, you will see beautiful sceneries typical of the region. Besides, you can meet and make friends with people of different colors and races. Finally, you can get to know the customs and living habits of the local people. Today people are so fond of travelling that tourism has bee one of the faster growing industries in most countries.The main reason why people travel is, perhaps, for pleasure. For example, having worked hard throughout the weekdays, people will find a widened trip to the nearby mountains or beaches a real relaxation. For another example, spending an annual holiday travelling abroad is an especially satisfying experience for those who do not have much of an opportunity to be away from their homelands. When people return from their travel, they will generally feel fresh and energetic, ready to work harder.Travelling is also one of the best means for learning. You may have read or heard about something but you can never get an accurate picture of it until you see it for yourself. Seeing is believing. Furthermore, if you area careful observer, you can learn much during your travel about the geography, biology, and history of the places you visit. No matter how well educated you are, there is always a lot for you to learn through travelling. The knowledge acquired from travel, as you will have found in your life, is no less valuable than that from any influential reference book.9. The World Population ExplosionThe human race has experienced a consistent increa