She ______ for more freedom in her work, which finally made her decide to start her own business.A. owedB. cravedC. sackedD. propelled

How Ozone Pollution Works Introduction to How Ozone Pollution Works The weather report on the radio or TV tells you that it is going to be sunny and hot and that an orange ozone alert has been issued. What is ozone What does an orange alert mean Why should you be concerned about it In this article, we will examine what ozone is, how it is produced, what health hazards it poses and what you can do to reduce ozone pollution. Ozone is a molecule of three oxygen atoms bound together (O3). It is unstable and highly reactive. Ozone is used as a bleach, a deodorizing agent, and a sterilization agent for air and drinking water. At low concentrations, it is toxic. Ozone is found naturally in small concentrations in the stratosphere, a layer of Earth’s upper atmosphere. In this upper atmosphere, ozone is made when ultraviolet light from the sun splits an oxygen molecule (O2), forming two single oxygen atoms. If a freed atom collides with an oxogen molecule, it becomes ozone. Stratospheric ozone has been called "good" ozone because it protects the Earth’s surface from dangerous ultraviolet light. Ozone can also be found in the troposphere, the lowest layer of the atmosphere. Tropospheric ozone (often termed "bad" ozone) is man-made, a result of air pollution from internal combustion engines and power plants. Automobile exhaust and industrial emissions release a family of nitrogen oxide gases (NOx) and volatile organic compounds (VOC), by-products of burning gasoline and coal. NOx and VOC combine chemically with oxygen to form ozone during sunny, high-temperature conditions of late spring, summer and early fall. High levels of ozone are usually formed in the heat of the afternoon and early evening, dissipating during the cooler nights. Although ozone pollution is formed mainly in urban and suburban areas, it ends up in rural areas as well, carried by prevailing winds or resulting from cars and trucks that travel into rural areas. Significant levels of ozone pollution can be detected in rural areas as far as 250 miles ( 150 km) downwind from urban industrial zones. Make Your Own Ozone Detector You can make ozone test strips to detect and monitor ozone levels in your own backyard or around your school. You will need: ・cornstarch ・filter paper (coffee filters work well) ・potassium iodide (can be ordered from a science education supplier such as Carolina Biological Supply or Fisher Scientific ) Basically, you make a paste from water, corn starch and potassium-iodide, and you paint this paste on strips of filter paper. You then expose the strips to the air for eight hours. Ozone in the air will react with the potassium iodide to change the color of the strip. You will also need to know the relative humidity, which you can get from a newspaper, weather broadcast or home weather station. Avoiding and Reducing Ozone When you inhale ozone, it travels throughout your respiratory tract. Because ozone is very corrosive, it damages the bronchioles and alveoli in your lungs, air sacs that are important for gas exchange. Repeated exposure to ozone can inflame lung tissues and cause respiratory infections. Ozone exposure can aggravate existing respiratory conditions such as asthma, reduce your lung function and capacity for exercise and cause chest pains and coughing. Young children, adults who are active outdoors and people with respiratory diseases are most susceptible to the high levels of ozone encountered during the summer. In addition to effects on humans, the corrosive nature of ozone can damage plants and trees. High levels of ozone can destroy agricultural crops and forest vegetation. Avoiding Ozone Exposure To protect yourself from ozone exposure, you should be aware of the Air Quality Index (AQI) in your area everyday--you can usually find it in the newspaper or on a morning weather forecast on TV or radio. You should also be familiar with the U.S. Environmental Protection Agency (EPA) guide for ozone-alert values. What do the numbers in the AQI mean The AQI measures concentrations of five air pollutants: ozone, sulfur dioxide, particulate matter, carbon monoxide and nitrogen dioxide. The EPA has chosen these pollutants as criteria pollutants, but these are not all of the pollutants in the air. These concentrations are compared to a standard set out in federal law. An index value of 100 means that all of the criteria pollutants are at the maximum level that is considered safe for the majority of the population. To reduce your exposure to ozone, you should avoid exercising during afternoon and early evening hours in the summer. Reducing Ozone Pollution There are several ways you can help to decrease ozone pollution: ・Limit using your automobile during afternoon and early evening hours in the late spring, summer and early fall. ・Do not use gasoline-powered lawn equipment during these times. ・Do not fuel your car during these times. ・Do not light fires or outdoor grills during these times. ・Keep the engine of your car or boat tuned, ・Make sure that your tires are properly inflated. ・Use environmentally safe paints, cleaning and office products (some of these chemicals are sources of VOC). ・Conserve energy. Besides personal attempts to reduce ozone pollution, the EPA has initiated more stringent air-quality standards (such as the Clean Air Act and its modifications) to reduce air pollution. Compliance with these standards by industries, manufacturers and state and local governments has significantly reduced the levels of many common air pollutants. With continued conservation and reduction practices, adherence to ozone- pollution warnings, research and government regulation, ozone-pollution levels should continue to fall. Perhaps future generations will not be threatened by this environmental pollutant. How can ozone be both good and bad The thing that determines whether ozone is good or bad is its location. Ozone is "good" when it is in the stratosphere. The stratosphere is a layer of the atmosphere starting at the level of about 6 miles (about 10 kilometers) above sea level. The stratosphere naturally contains about six parts per million of ozone, and this ozone is very beneficial because it absorbs UV radiation and prevents it from reaching us. Ozone is "bad" when it is at ground level. Ozone is a very reactive gas that is hard on lung tissue. It also damages plants and buildings. Any ozone at ground level is a problem. Unfortunately, chemicals in car exhaust and chemicals produced by some industries react with light to produce lots of ozone at ground level. In cities, the ozone level can rise to a point where it becomes hazardous to our health. That’s when you hear about an ozone warning on the news.High levels of ozone are usually dissipating______. A．in the heat of the afternoon and early eveningB．during sunny, high-temperature conditions of late spring, summer and early fallC．during the cooler nightsD．during the summer

There are at least 8 million unique species of life on the planet, if net far more, and you could be forgiven for believing that all of them can be found in Andasibe. Walking through this rain forest in Madagascar is like stepping into the library of life. Sunlight seeps through the silky fringes of the Ravenea louvelii, an endangered palm (棕榈树) found, like so much else on this African island, nowhere else. Madagascar which separated from India 80 million to 100 million years ago before eventually settling off the southeastern coast of Africa, is in many ways an Earth apart. All that time in geographic isolation made Madagascar a Darwinian playground, its animals and plants evolving into forms utterly original. Some 90% of the island’s plants and about 70% of its animals arc endemic, meaning that they arc found only in Madagascar. But what makes life on the island unique also makes it uniquely vuhnerable, which means if we lose these animals on Madagascar, they’re gone forever. That loss seems likelier than ever because the animals are under threat as never before. Once lushly forested, Madagascar has seen more than 80% of its original vegetation cut down or burned since humans arrived at least 1500 years ago, fragmenting habitats and leaving animals effectively homeless. Unchecked hunting wiped out a number of large species, and today mining, logging and energy exploration threaten those that remain. It has an area the size of New Jersey in Madagascar that is still under forest, and all this incredible diversity is crammed into it. Madagascar is a conservation hot spot a term for a region that is very biodiverse and particularly threatened--and while that makes the island special, it is hardly alone. Conservationists estimate that extinctions worldwide are occurring at a pace that is up to 1 000 times as great as history’s background rate before human beings began scattering. Worse, that die-off could be accelerating. There have been five extinction waves in the planet’s history―including the Permian (二叠纪的) extinction 250 million years ago, when an estimated 70% of all terrestrial animals and 96 % of all marine creatures vanished, and, most recently, the Cretaceous (白垩纪的) event 65 million ),ears ago, which ended the reign of the dinosaurs. Though scientists have directly assessed the viability of fewer than 3% of the world’s described species, the sample polling of animal populations so far suggests that we may have entered what will be the planet’s sixth great extinction wave. And this time the cause isn’t an unsteady planet or volcanoes. It’s us. Through our growing numbers, our thirst for natural resources and, most of all, climate change-- which, by one reckoning, could help carry off 20% to 30% of all species before the end of the century-- we’re shaping an Earth that will be biologically exhausted. A 2008 assessment by the: International Union for Conservation of Nature found that nearly 1 in 4 mammals worldwide were at risk for extinction, including endangered species. Over fishing and acidification of the oceans are threatening marine species as diverse as the corals. Scary for conservationists, yes. but the question arises: Why should it matter to the rest of us After all, nearly all the species that were ever alive in the past are gone today. Evolution demands extinction. When we’re using the term extinction to talk about the fate of the US auto industry, does it really matter if we lose species like the Yangtze River dolphin and the golden toad, all of which have effectively disappeared in recent years What docs the loss of a few species among millions matter For one thing, we’re animals too, dependent on this planet like every other form of life. The more species living in an ecosystem, the healthier and more productive it is, which matters for us--a recent study by the World Wildlife Fund (WWF) estimates the economic value of the Amazon rain forest’s ecosystem services to be up to 100 per hectare (about 2.5 acres). When we pollute and deforest and make a mess of the ecological web, we’re taking out mortgages on the Earth that we can’t pay back--and those loans will come due. Then there are the undiscovered organisms and animals that could serve as the basis of needed medicines as the original ingredients of aspirin were derived from the herb meadowsweet unless we unwittingly destroy them first. Forests razed can grow back., polluted air and water can be cleaned, but extinction is forever. And we’re not talking about losing just a few species. In fact, conservationists quietly acknowledge that we’ve entered an age of triage (挑选), when we might have to decide which species can truly be saved. The worst-case plot of habitat loss and climate change and that’s the pathway we seem to be on-show the planet losing hundreds of thousands to millions of species, many of which we haven’t even discovered yet. The result could be a virtual extinction of much of the animal world and an irreversible poverty of our planet. Hmnans would survive, but we would have doomed ourselves to what naturalist E.O. ’Wilson calls the Eremozoic Era the Age of Loneliness. So if you care about tigers and rhinos, if you believe Earth is more than just a home for 6.7 billion human beings and counting, then you should be scared. But fear shouldn’t leave us paralyzed. Environmental groups worldwide are responding with new methods to new threats to wildlife. In hot spots like Madagascar and Brazil. conservationists are working with locals on the ground, ensuring that the protection of endangered species is tied to the welfare of the people who live closest to them. A strategy known as avoided deforestation goes further, incentivizing environmental protection by putting a price on the carbon locked in rain forests and allowing countries to trade credits in an international market, provided that the carbon stays in the trees and is not cut or burned. And as global warming forces animals to migrate in order to escape changing climates, conservationists are looking to create protected corridors that would give the species room to roam. It’s uncertain that any of this will stop the sixth extinction wave, let alone preserve the biodiversity we still enjoy, but we have no, choice but to try. We have a window of opportunity, but it’s slamming shut. Madagascar, which is called the "hottest of the hot spots", is where all the new strategies can be road tested. In 2003, after decades when conservation was barely on the government’s agenda, then-President Marc Ravalomanana announced that the government would triple Madagascar’s protected areas over the following five years. That decision helped under funded parks like Andasibe’s, which protects some of the last untouched forest on the is land. "You can’t save a species without saving the habitat where it lives," says WWF’s Roberts. Do that right, and you can even turn a profit in the process. In Madagascar, half the revenues from national parks are meant to go leo the surrounding communities. The reserves in turn help sustain an industry for local guides. In a country as poor as Madagascar, where 61% of the people live on less than 1 a day, it makes sense to give locals an economic stake in preserving wildlife rather than destroying it. The corridors created by CI’s Andasibe tree-planting program show how a small tweak can reduce the species killing effects of climate change--but also how longer-term fixes are needed. Fragmented habitats are problematic because many endangered species wind up trapped in green oases surrounded by degraded land. As global warming changes the climate, species will try to migrate, often right into the path of development and extinction. What good is a nature reserve--fought for, paid for and protected--if global warming renders it unlivable Climate change could undermine the conservation work of whole generations. It turns out you can’t save species without saving the sky. That will mean reducing carbon emissions as fast as possible. In the US, the CBD has made an art out of using the Endangered Species Act, which mandates that the government prevent the extinction of listed species, to force Washington to act on global warming. The CBD’s Siegel led a successful campaign to get the Bush Administration to list the polar bear as threatened by climate change, and we expect more species to follow.Why are conservationists cooperating with local people in Madagascar and Brazil A．Because they care about tigers and rhinos.B．Because they are scared by the fact and want to give up.C．Because they want to associate the protection with welfare of the locals.D．Because they want to avoid deforestation.

We slept with the light ________ all night long last night.A. burntB. to burnC. being burntD. burning

The introduction of self-driving cars could have a major impact on how older adults go about their daily lives. It is hoped these cars will help reduce the social isolation and loneliness we often experience as we get older. Additionally, this technology has the potential to enable a greater level of independence for disabled people, both those with visible disabilities and those with non-visible disabilities.In fact, connectivity and driver-assistance features are already common in cars. Today, vehicles can connect to the Internet to provide drivers with information on road, traffic and weather conditions. They can also take over limited parts of the driving task, for example using advanced emergency braking to help avoid collisions and adaptive cruise control to increase fuel efficiency and reduce driver fatigue.36. What does the author say about the influence of self-driving cars?A They enable older adults to stay in their own homes.B They provide help for the isolated young people.C They make it possible for the disabled to be more independent.

It.s sometimes difficult to see the difference between a fad and a trend

31.以前我们多数人住在没有卫生间的旧房子里。A. In pass we mostly lived in old houses with bathrooms .B. In the past we mostly lived in old houses without bathrooms.

There was a heated discussion about customer service at the meeting until the manager came up with a great idea.A. 经理提出的关于客户服务的好主意，在会议上引起了大家的热烈讨论。B. 经理到会之前，会议还在对那个客户提出的合理建议进行热烈的争论。C. 会议就客服问题进行了热烈讨论，直到经理提出一个绝妙主意才停止。D. 会议一直在热烈讨论客服问题，直到结束时经理才想出了一个好主意。

Englishmen introduce each other by first name, without titles, and sometimes by just the last name. If one person is introduced to another person by first name, the person can address him or her by first name the next time they meet. The only exception would be for someone who holds an important position, such as the university president. Occasionally. Englishmen shake hands with each other, but they think with friends once in a lifetime is often considered enough. They use"Are you all right?"rather than the formal greeting"How are you? from our textbooks. When they get off the bus or buy things from shops, they say Cheers'to the drivers or sellers instead of Thanks'or"Bye". Most Englishmen never hug or kiss other men. They leave that to football players and foreigners. Women may kiss on one or both cheeks. Men may also kiss women in greeting, but only on the cheek. In public places, the English make efforts not to touch strangers even by accident. If such an accident should happen, they would apologize, but eye contact should be avoided. The queue is one of the few places where the English are allowed to talk to each other without having been formally introduced. 1/5 21. When Englishmen meet each other, they may _. A hug each other B shake hands C Kiss on the cheeks D say"How do you do?

The purpose of an advertisement is to make people respond—to make them react to an idea.A. 广告的目的是让人们作出响应——让他们响应某一理念。B. 学习的目的是让人们作出响应——让他们响应某一理念。C. 唱歌的目的是让人们作出响应——让他们响应某一理念。D. 画画的目的是让人们作出响应——让他们响应某一理念。