A new study has found no evidence that sunscreen, commonly used to reduce the risk of skin cancer, actually increase the risk.
Researchers from the University of Iowa based their findings on a review of 18 earlier studies that looked at the association between sunscreen use and melanoma (黑素瘤). They said that they found flaws in studies that had reported associations between sunscreen use and higher risk of melanoma
Most health experts believe that by protecting the skin from the harmful effects of the sun, sunscreen helps prevent skin cancer, which is increasing in incidence (发生率) faster than any other cancer in the United States.
But questions has been raised about sunscreen and whether it may has opposite effect, perhaps by allowing people to remain exposed to the sun longer without burning.
The researchers said that among the problems with some earlier studies is that they often failed to take into account that those people most at risk for skin cancer--- people with fair skin and freckles (雀斑), for example--- are more likely to use sunscreen. As a result, it may appear that sunscreen users get cancer more often.
The studies, which generally relied on volunteers to recall their sunscreen use, were also unable to prove how well the products had been applied, said the new study.The underlined word “flaws” in the 2nd paragraph most probably means ______.
| A．evidence | B．facts | C．faults | D．failures |
People with fair skin and freckles .
| A．seldom use sunscreen | B．are more in danger of skin cancer |
| C．can be free from the harm of the sun | D．often expose themselves to the sun |
We can learn from the passage that ______.
| A．sunscreen users get skin cancer more often |
| B．the volunteers have proved the effect of sunscreen |
| C．the new study was based on the experiences of volunteers |
| D．the number of skin cancer patients is increasing in America |
Which of the following can be the title for this passage?
| A．Sunscreen to Prevent Skin Cancer | B．Sunscreen to Increase Skin Cancer |
| C．Skin Cancer Caused by Sunscreen | D．Skin Cancer Caused by Freckles |
As the railroads and the highways shaped the American West in the past centuries, a new electrical generating(发电)and transmission (输送) system for the 21st century will leave a lasting mark on the West, for better or worse. Much of the real significance of railroads and highways is not in their direct physical effect on the scenery, but in the ways that they affect the surrounding community. The same is true of big solar plants and the power lines that will be laid down to move electricity around.
The 19 th century saw land grants(政府拨地) offered to railroad companies to build the transcontinental railroads, leaving public land in between privately owned land. In much of the West, some of the railroad sections were developed while others remained undeveloped, and in both cases the landownership has presented unique challenges to land management. With the completion of the interstate highway system, many of the small towns, which sprang up as railway stops and developed well, have lost their lifeblood and died.
Big solar plants and their power lines will also have effects far beyond their direct footprint in the West. This is not an argument against building them. We need alternative energy badly, and to really take advantage of it we need to be able to move electricity around far more readily than we can now.
So trade-offs will have to be made. Some scenic spots will be sacrificed. Some species(物种) will be forced to move, or will be carefully moved to special accommodations. Deals will be struck to reduce the immediate effects.
The lasting effects of these trade-offs are another matter. The 21st century development of the American West as an ideal place for alternative energy is going to throw off a lot of power and money in the region. There are chances for that power and money to do a lot of good. But it is just as likely that they will be spent wastefully and will leave new problems behind, just like the railroads and the highways.
The money set aside in negotiated trade-offs and the institutions that control it will shape the West far beyond the immediate footprint of power plants and transmission lines. So let’s remember the effects of the railroads and the highways as we construct these new power plants in the West.What was the problem caused by the construction of the railways?
| A．Small towns along the railways became abandoned. |
| B．Land in the West was hard to manage. |
| C．Some railroad stops remained underused. |
| D．Land grants went into private hands. |
What is the major concern in the development of alternative energy according to the last two paragraphs?
| A．The use of money and power. |
| B．The transmission of power. |
| C．The conservation of solar energy. |
| D．The selection of an ideal place. |
What is the author’s attitude towards building solar plants?
| A．Disapproving. | B．Approving. | C．Doubtful. | D．Cautious. |
Which is the best title for the passage?
| A．How the Railways Have Affected the West |
| B．How the Effects of Power Plants Can Be Reduced |
| C．How Solar Energy Could Reshape the West |
| D．How the Problems of the Highways Have Been Settled |
You never see him, but they're with you every time you fly. They record where you are going, how fast you're traveling and whether everything on your airplane is functioning normally. Their ability to endure almost any disaster makes them seem like something out of a comic book. They're known as the black box.
When planes fall from the sky, as a Yemeni airliner did on its way to Comoros Islands in the India ocean on June 30, 2009, the black box is the best bet for identifying what went wrong. So when a French submarine (潜水艇) detected the box's homing signal five days later, the discovery marked a huge step toward determining the cause of a tragedy in which 152 passengers were killed.
In 1958, Australian scientist David Warren developed a flight-memory recorder that would track basic information like altitude and direction. That was the first mode for a black box, which became a requirement on all U.S. commercial flights by 1960. Early models often failed to withstand crashes, however, so in 1965 the box was completely redesigned and moved to the rear of the plane – the area least subject to impact – from its original position in the landing wells (起落架舱). The same year, the Federal Aviation Authority required that the boxes, which were never actually black, be painted orange or yellow to aid visibility.
Modern airplanes have two black boxes: a voice recorder, which tracks pilots' conversations, and a flight-data recorder, which monitors fuel levels, engine noises and other operating functions that help investigators reconstruct the aircraft's final moments. Placed in an insulated (隔绝的) case and surrounded by a quarter-inch-thick panels of stainless steel, the boxes can stand massive force and temperatures up to 2,000℉. When submerged, they're also able to emit signals from depths of 20,000 ft. Experts believe the boxes from Air France Flight 447, which crashed near Brazil on June 1,2009, are in water nearly that deep, but statistics say they're still likely to turn up. In the approximately 20 deep-sea crashes over the past 30 years, only one plane's black boxes were never recovered.What does the author say about the black box?
| A．It is an indispensable device on an airplane. |
| B．The idea for its design comes from a comic book. |
| C．Its ability to avoid disasters is incredible. |
| D．It ensures the normal functioning of an airplane. |
What does the underlined word in the 3rd paragraph mean?
| A．witness | B．experience | C．resist | D．ensure |
Why was the black box redesigned in 1965?
| A．New materials became available by that time. |
| B．Too much space was needed for its installation. |
| C．The early models didn't provide the needed data. |
| D．The early models often got damaged in the crash. |
What do we know about the black boxes from Air France Flight 447?
| A．There is an urgent need for them to be reconstructed. |
| B．There is still a good chance of their being recovered. |
| C．They have stopped sending homing signals. |
| D．They were destroyed somewhere near Brazil. |
This Teaching Assistant Level 3 course is designed for people who either are, or wish to become a teaching assistant. Teaching assistants carry out their tasks under the direction of the class teacher. This is a fully supported home study course, and the help is available whenever you need it --- either online or over the phone. There is a huge demand for teaching assistants around the country but also many thousands of applicants for these positions. Having this Teaching Assistant Level 3 qualification will help you stand out from other applicants. Our Level 3 Teaching Assistant course is similar to the NVQ (National Vocational Qualification) Level 3 because it is an equivalent (同等的) level of learning.
The teaching assistant is able to contribute in four main areas:
Supporting the teacher
Supporting the pupil
Supporting the school
Supporting the curriculum
The salary a teaching assistant is expected to earn a year:
London fringe (外围):￡16,856 - ￡26,052
Outer London: ￡18,789 - ￡27,992
Inner London: ￡19,893 - ￡29,088
Rest of England and Wales: ￡15,817 - ￡25,016
The fee and the time of enrolment (入学)
Enroll for only a ￡35 deposit. Teaching Assistant Level 3 is only ￡345. To help you on your way towards achieving your qualification, we are offering all of our potential students a ￡115 reduction in their enrolment fees for June. The normal fee for this course is ￡460 but for this month it has been reduced to only ￡345. There has never been a better time to start learning and take that first step towards a brighter future!
100% money back guarantee, if you are not satisfied. That’s why we’ll happily give you your money back on any course returned within 7 days. It’s easy for you to enroll now by telephone 01223 923 913. You can get free friendly help and advice from 9:00 am to 4:00 pm, on Monday to Friday. Call 01223 923 915. How can people study this Teaching Assistant Level 3 course?
| A．Go to the night school. | B．Go to the full-time school. |
| C．Study at home at any time. | D．Study at weekends or vacations. |
What’s the teaching assistant’s task?
| A．Listening to the teacher’s lecture all the time. |
| B．Only helping teachers prepare their lessons. |
| C．Helping promote effective learning and teaching. |
| D．Often giving lessons in place of the formal teacher. |
If a teacher assistant earns ￡28,000 a year , he probably works in ______.
| A．downtown Wales | B．the fringe of London |
| C．outer London | D．downtown London |
How much should you pay in June if you have paid the deposit?
| A．￡35 | B．￡310 | C．￡345 | D．￡460 |
It's not a new phenomenon, but have you noticed how many nouns are being used as verbs? We all use them, often without noticing what we're doing.
I was arranging to meet someone for dinner last week, and I said “I’ll pencil it in my diary”, and my friend said “You can ink it in”, meaning that it was a firm arrangement not a tentative one!
Many of these new verbs are linked to new technology. An obvious example is the word fax. We all got used to sending and receiving faxes, and then soon started talking about faxing something and promising we'd fax it immediately. Then along came email, and we were soon all emailing each other madly. How did we do without it? I can hardly imagine life without my daily emails.
Email reminds me, of course, of my computer and its software, which has produced another couple of new verbs. On my computer I can bookmark those pages from the World Wide Web that I think I'll want to look at again, thus saving all the effort of remembering their addresses and calling them up from scratch. I can do the same thing on my PC, but there I don't bookmark; I favorite—coming from “favorite pages”, so the verb comes from an adjective not a noun.
Now my children bought me a mobile phone, known simply as a mobile and I had to learn yet more new verbs. I can message someone, that is, I can leave a message for them on their phone. Or I can text them, write a few words suggesting when and where to meet, for example. How long will it be before I can mobile them, that is, phone them using my mobile? I haven’t heard that verb yet, but I’m sure I will soon. Perhaps I’ll start using it myself!“I’ll pencil it in my diary” in the second paragraph probably means .
| A．it was a firm arrangement |
| B．he prefers a pencil to a pen |
| C．the arrangement should be written as a diary |
| D．it was an uncertain arrangement |
A website address can be easily found if it has been______.
| A．favorited | B．messaged | C．emailed | D．texted |
Which of the following has not been used as a verb yet?
| A．message | B．mobile | C．email | D．page |
The best title for this passage is____.
| A．Technology and Language. | B．Development of the English language |
| C．New Technology and New words | D．New Verbs from Nouns |
Teens’ lives hit by economy
Some teenagers are crossing their dream colleges off their lists. Others are thinking of skipping（略过）their senior trips or reducing prom(毕业舞会)costs. Many are finding their work hours cut while their expenses rise.
So, who exactly is punishing them？Is it their parents, teachers or employers？No, it’s the economy（经济状况）.
If you are like most teenagers, you probably don’t understand what “recession”, “negative economic growth” and “subprime mortgage crisis (次贷危机)”actually mean. And you probably don’t spend your days watching the ups and downs of the stock market.
It’s safe to say that most teens don’t know much about the economy except for one thing：it’s bad. But just how exactly is the economy affecting teens?
“The single largest thing I have noticed is the recession’s ability to affect my college choice, “said Heather Richars from Downey High School in California, US. “With the economic situation the way it is, I have thought less about going to a private or out-of-state university, and more about public schools in California, mainly because of the price of tuition, “said Richars. “I had been a fan of attending a private school up until this year.”
The economy cuts into other areas of teenagers’ lives, too.
Joey Camarda, a student at Modesto High School in California, who works at an ice cream store, said,“ Probably due to the economy, I have been getting less hours at my job, and because of that, I am not getting enough money to help pay for college.”
Tara Mooney, a senior at Beyer High School, has also begun to notice that money is tight.
“Things are getting expensive,” she said. “When it comes to applying for colleges and wanting to go on senior trips, I have to pick and choose instead of doing it all.”The purpose of writing the passage is mainly to tell us ________.
| A．the economic recession has had a big effect on teens’ work, life and study |
| B．teenagers are now having difficulty in deciding which colleges to apply for |
| C．teenagers don’t know much about the economic recession |
| D．teenagers are considering giving up their senior trips to save money |
Because of the bad economic situation, Heather Richars will most probably ________.
| A．go to a private university |
| B．attend an out-of-state college |
| C．attend a public college in California |
| D．find a good university as he planned |
How has Joey Camarda found the recession affects him?
| A．He has to find more part-time jobs. |
| B．He has to help his mother do more chores. |
| C．He has found that he had more time to study. |
| D．His plan to pay for college will be hard to realize. |
What can we conclude from the passage?
| A．Parents punish their teens by giving them less money. |
| B．Most teens understand what negative economic growth means. |
| C．Teenagers are finding it harder to do what they want than before. |
| D．Teenagers have realized the importance of managing their own money. |
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