The hole in the earth's protective ozone layer（臭氧层）won't repair itself until about two decades later than had been expected, scientists announced.
The ozone layer blocks more than 90 percent of the sun's ultraviolet radiation（紫外线辐射）, helping to make life on Earth possible. For many dacades, ozone was depleted（削减） by chlorine and bromine gas in the air. A hole in the ozone layer formed over the Southern Hemisphere.
Computer models had forecast that the hole would fill back in by 2050. An improved computer model forecasts the recovery won't occur until 2068. The model, fed with fresh data from statellites and airplanes, was supported by the fact that it accurately reproduced ozone levels in the Antarctic stratosphere（平流层）over the past 27 years.
The ozone hole is actually more of a broad region with less ozone than ought to occur naturally. It is not limited to Antarctica, as is often believed.
Over areas that are farther from the poles like Africa or the US, the levels of ozone are only three to six percent below natural levels. Over Antarctica, ozone levels are 70 percent lower in the spring. This new method allows us to more accurately estimate（估计）ozone-depleting gases over Antarctica, and how they will decrease over time, reducing the ozone hole area.
Paul Newman, a scientist,said that the ozone hole has not started to become smaller as quickly as expected. They figure it will not become much smaller until 2018, after which time the recovery should proceed more quickly. And the hole will not be filled in again until 2065.
【小题1】According to the passage, the ozone layer _______

Each year, road accidents kill a million people and injure millions more . The economic costs are greatest for developing countries . Earlier this year , the United Nations called for a campaign to improve road safety .
One way to avoid accidents is better driving . Another is better roads and bridges . Engineers in the Unites States have designed ten new concrete mixtures that they think could make bridges last longer .
Professor Paul Tikalsky leads the experiments by a team at Pennsylvania State University . He says bridges made of concrete now last about twenty-five to thirty-five years . But he says the new mixtures might extend that to seventy –five or even one-hundred years .
Concrete is made of stone , sand , water and cement(水泥). The materials in the cement hold the concrete together . Ancient Romans built with concrete . Yet strengthened concrete bridges did not appear until the late 1800s . People keep looking for new ways to improve concrete . Professor Tikalsky says it is one of the most complex of all chemical systems .
The new mixtures designed by his team contain industrial waste products . He says these make the concrete better able to resist damage from water and salt over time . One of the products is fly ash . This is released into the air as pollution when coal is burned .
Professor Tikalsky says particles (颗粒)of fly ash are almost exactly the same size and chemical structure as Portland cement . This is the most costly material in concrete . So using fly ash to replace some of it would save money .
The federal government is paying for part of the research . Engineers anywhere can use the technology . Professor Tikalsky says some of the ideas have already been put to use in China , the Philippines and other countries .
【小题1】Why did the United Nations launch the campaign ?

Growing up on a tobacco farm, Emma Avery was used to hard times. When she was seven, her family’s farmhouse burned to the ground. Her father made a temporary (临时的) shelter, where eight people had to sleep in two beds. As soon as Emma and her four brothers and two sisters were big enough, they were out in the fields.

     Emma would find her comfort in school, even as a C student, thanks to one teacher. When she moved on to middle school, Emma was alarmingly far behind her classmates. She kept her head down, trying not to be noticed, struggling to catch up, and feeling like an outsider.

     Then one day, when Emma was 16, a teacher named Mr. Potts changed everything. Looking his students in the eye, Mr. Potts said, "Being a C student does not mean you do not have a valuable contribution to make. Some of you have to work in the fields in the evening and do not have time to study. But if you do your best, you have a gift to give."

     The teacher’s words made Emma believe she could do well, and she worked harder. In the end she won a scholarship to St. Paul’s College, graduated with a degree in elementary education in 1967, and got a job in the public-school system. Then, at George Washington University, she received a master’s in education in 1970, and afterwards in the same year she married Ron Smothers.

     Over the next six years, Emma taught in public schools in Miami. In 1976, after saving $10,000, she opened her first restaurant in Los Angeles. Eventually Emma stopped teaching, and her business expanded (扩展) to six restaurants.

     In gratitude (感激) for what she has been able to achieve, Emma donates a lot. She has no idea how much money she’s given away. She says, "Those I want to help are the C students who just need help, direction and confidence."

1.The first paragraph serves to show that Emma ______.

A．was poor and had no time to study          B．was born on a tobacco farm C．was sad to lose her house D．was kind enough to help support the family

2.From the text we learn that Emma ______.  

A．won a scholarship to George Washington University                 B．was unsuccessful as a businesswoman C．was thankful to Mr. Potts             D．disliked teaching, and gave up the job

3.From the second paragraph we can infer that Emma was ______.

A．unintelligent       B．unconfident        C．hard-working       D．Considerate

4.The text mainly wants to tell us ______.

A．confidence is the first step to success        B．memory of the past is the teacher of the future C．something attempted, something done       D．nothing is impossible to a willing heart

Multitasking
People who multitask all the time may be the worst at doing two things at once, a new research suggests. The findings, based on performances and self-evaluation by about 275 college students, indicate that many people multitask not out of a desire to increase productivity, but because they are easily distracted (分心) and can’t focus on one activity. And “those people turn out to be the worst at handling different things,” said David Sanbonmatsu, a psychologist at the University of Utah.
Sanbonmatsu and his colleagues gave the students a set of tests and asked them to report how often they multitasked, how good they thought they were at it, and how sensation-seeking (寻求刺激) or imperative (冲动) they were. They then evaluated the participants’ multitasking ability with a tricky mental task that required the students to do simple mathematical calculations while remembering a set of letters.
Not surprisingly, the scientists said, most people thought they were better than average at multitasking, and those who thought they were better at it were more likely to report using a cellphone while driving or viewing multiple kinds of media at once. But those who frequently deal with many things at the same time were found to perform the worst at the actual multitasking test. They also were more likely to admit to sensation-seeking and impulsive behavior, which connects with how easily people get bored and distracted.
“People multitask not because it’s going to lead to greater productivity, but because they’re distractible, and they get sucked into things that are not as important.” Sanbonmatsu said.
Adam Gazzaley, a researcher at the University of California, San Francisco, who was not a member of the research group, said one limitation of the study was that it couldn’t find out whether people who start out less focused   toward multitasking or whether people’s recognizing and understanding abilities change as a result of multitasking.
The findings do suggest, however, why the sensation-seeker who multitask the most may enjoy risky distracted driving. “People who are multitasking are generally less sensitive to risky situations.” said Paul Atchley, another researcher not in the group. “This may partly explain why people go in for these situations even though they’re dangerous.”
【小题1】 The research led by Sanbonmatsu indicates that people who multitask       .

A 7.0 magnitude（级）earthquake killed more than 230,000 people in Haiti. Then an 8.8 magnitude quake killed more than 900 people in Chile. And few weeks later, a 6.0 magnitude quake struck rural eastern Turkey, killing at least 57 people.
The earthquakes kept coming hard and fast.   1 It’s not. The problem is what’s happening above ground, not underground, experts say.
  2 They’re rapidly putting up buildings that can’t stand up to earth quakes, scientists believe.
And news reports and better earthquake monitoring make it seem as if earth quakes are increasing all the time.
On average, there are 134 earthquakes a year that have a magnitude between 6.0 and 6.9. So far this year there have been 40 earthquakes—more than in most years for that time period. But that’s because the 8.8 quake in Chile caused a large number of strong aftershocks.
Also, it’s not the number of quakes, but their destructive effects that gain attention. The death is largely due to building standards,   3  Paul Earle, a US seismologist, called for better building standards in the world’s big cities.
Of the 130 cities worldwide with populations of more than I million, more than half are likely to be hit by earthquakes.   4 “If you have a problem feeding yourself, you’re not really going to worry about earthquakes,” said Paul.
The earthquakes made everyone start to think   5  “People are paying attention to the violent planet we’re always lived on. Come back an another six moths if there has been no earthquakes, most people will have forgotten it again,” said US disaster researcher Dennis Mileti.