While many people aren't getting enough calcium （鈣），new research cautions that some people may have the opposite problem：They could be getting too much.Americans spend more than ﹩1 billion a year on calcium supplements （補(bǔ)充劑） in hopes of delaying osteoporosis，the brittle bone disease that cripples many elderly women and some men.Yet recent studies link calcium supplements to a higher risk of heart attacks.Last month，the U.S.Preventive Services Task Force issued a draft recommendation against taking calcium and vitamin D，saying there wasn't enough evidence of benefit to justify the risk.
For generations of Americans who grew up encouraged to drink milk to maintain strong bones，the reports raised troubling questions：Is calcium not so important after all？Are the supplements unsafe？And how much is too much？ "It's gotten very confusing but it doesn't need to be，" says Ethel Siris，director of the Toni Stabile Osteoporosis Center in New York.How much calcium people need varies by age and gender. "Adults generally need 1，000 mg daily，rising to 1，200 mg for women over 50 and men over 70，according to guidelines issued in 2010.Children need 1，300 mg daily during the peak growing years of 9 to 18. "
People also need sufficient levels of vitamin D to absorb the calcium.The IOM recommends 600 international units a day for most adults，and 800 daily after age 70，although many physicians recommend more.It is difficult to take in that much vitamin D from food sources，so experts say many people should take vitamin D in supplement form.
Getting adequate （充足的） calcium from food is easier.For example，8 ounces of milk or 6 ounces of yogurt has 300 mg of calcium，and one cup of spinach has 270 mg.
But studies linking calcium supplements to heart attack have made experts more cautious of excess calcium than before.A study of 24，000 Germans published in the journal Heart last month，found that those who got their calcium exclusively from supplements were more than twice as likely to have a heart attack as those who took no supplements.
Exactly how calcium supplements might contribute to heart attacks baffles cardiologists （心臟病學(xué)家）. "Nobody has associated the calcium in your bloodstream with calcification （鈣化） in your arteries，" says Nieca Goldberg，medical director of the Joan H.Tisch Center.Still，she says she now urges patients get their recommended calcium from food than from supplements to avoid possible problems.
Osteoporosis experts also urge patients not to take more than the recommended amount of calcium. "People should definitely stop taking two big calcium supplements a day，" says Dr.Dawson-Hughes.Even if the risks remain unclear，taking more than the body can absorb doesn't benefit bones， "so it's not worth any risk. " She adds.
（1）What is Ethel Siris' opinion on taking calcium supplements？ CC
A．Taking calcium supplements is unsafe.
B．Adults need more calcium than children.
C．Age and gender determine how much calcium is needed.
D．It is safer to take calcium from food than from supplements.
（2）What does the underlined word "baffle" in Paragraph 6 mean？ DD
A．Interest.
B．Amaze.
C．Frighten.
D．Puzzle.
（3）What can we learn from the passage？ BB
A．Taking two calcium supplements a day is good for health.
B．It might be wiser to take recommended calcium from food.
C．It is easy for people to obtain enough Vitamin D from food.
D．The benefits of taking calcium supplements outweigh its risks.
【答案】C；D；B
【解答】
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發(fā)布：2024/5/27 14:0:0組卷：7引用：2難度：0.3
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1．Most of us spend our lives seeking the natural world.We go fishing，sit in the garden，have a picnic，live in the suburbs or go to the seaside.The most popular leisure activity in Britain is going for a walk.When joggers jog，they don't run on the streets.Every one of them tends to go to the park or the river.
But despite this，our children are growing up naturedeprived（剝奪）.I spent my boyhood climbing trees.These days，children are robbed of the ancient freedom，due to problems like crime，traffic，the loss of the open space and strange new ideas about what is best for children，that is to say，things that can be bought，rather than things that can be found.
The truth is to be found elsewhere.A study in the US：families had moved to better housing and the children were assessed for ADHD—Attention Deficit Hyperactivity Disorder（注意力缺陷多動癥）.Those whose accommodation had more natural views showed an improvement of 19%；those who had the same improvement in material surroundings but no nice view improved just 4%.
ADHD is one of the great problems of modern childhood.One study after another indicates that contact with nature gives huge benefits to ADHD children.However，we spend money on drugs rather than on green places.
The life of old people is measurably better when they have access to nature.The increasing concern for the growing population of old people is in quality rather than quantity of years.And study after study finds that a garden is the single most important thing in finding that quality.Even problems with crime and aggressive behaviour are reduced when there is contact with the natural world.
We need the wild world.It is essential to our wellbeing，our health and our happiness.
（1）According to the author，people enjoyto seek nature.
A．jogging on the street
B．running in the gym
C．shopping in the supermarket
D．sitting in the garden
（2）From the second paragraph，we can see that.
A．Children don't want to approach nature
B．children probably spend less time in nature nowadays
C．climbing trees will certainly do good to the children
D．children tend to be happier as a result of their material satisfaction
（3）In what way do people benefit from their contact with nature？
A．Children with ADHD can be cured.
B．Children's performance at school is greatly improved.
C．Problems with crime and violent behavior will easily be solved.
D．A garden nearby improves the quality of old people's life.
（4）what is the main idea of this passage？
A．Access to nature improves our life.
B．Nature treats children for ADHD.
C．Getting close to nature reduces crime.
D．Man can't live without natural areas.發(fā)布：2025/1/6 16:30:6組卷：0引用：1難度：0.5 -
2．It is widely believed that biodiversity（生物多樣性）is promoted to save species.But in reality species exist only as part of ecosystems and cannot survive unless their ecosystems are protected along with as much as possible of the diversity they contain.
Protecting habitats（棲息地）is important for keeping biodiversity.In 2003，over 102，000 habitats covering nearly 19 million square kilometres，or 11.5% of the world's land surface，were under some form of protection.Though this is a great improvement since 1962，when just 1，000 protected habitats were listed，it is still not considered enough to stop the ecocide that is endangering the world's biodiversity.
For a number of environmentalist，protecting the world's 25 biodiversity hotspots（熱點地區(qū)）is critical to saving habitats and species.But many hotspots are endangered already，having lost up to three-quarters of their original plants.
The poor state of most biodiversity hotspots results directly from population growth and migration（遷移） into these areas.A study found that by the mid-1990s around 1.1 billion people lived in these hotspots.Moreover，the annual population growth rate in these areas was 1.8%，higher than the global average of 1.4%.The PAI report concluded that human-related environmental changes will continue to put pressure on hotspots.Therefore，keeping biodiversity requires paying close attention to population size.
Protecting hotspots is not simply a matter of putting up fences and employing guards.The best results are achieved when local people are educated about the value of wildlife，and actually gain a share of the benefits from eco-tourism.Only then do they have a chance to see the benefits of protecting hotpots.
（1）What can we infer from paragraph 1？
A．The loss of any species can affect humans.
B．Endangered species are paid more attention to by humans.
C．Species can still survive when their ecosystems are destroyed.
D．Ecosystem protection is as important as diversity protection.
（2）What does the underlined word "ecocide" in paragraph 2 mean？
A．Ecosystem protection.
B．Reduction of the number of species.
C．Serious damage to habitats.
D．Habitats protection.
（3）What's the direct cause of the terrible state of the hotspots？
A．Population growth in hotpots.
B．Migration out of these areas.
C．Global warming.
D．The global average population growth rate.
（4）What's the author's opinion on protecting the hotspots？
A．It's simple to carry out.
B．It leads to the increase of tourists.
C．It's closely connected with local people.
D．It suggests that the local people are well educated.發(fā)布：2025/1/6 16:30:6組卷：0引用：1難度：0.5 -
3．New editions of Roald Dahl's classic books，such as Charlie and the Chocolate Factory and Matilda，are now available in bookstores.Some passages relating to weight，mental health，gender and race were changed.The changes made by Puffin Books，a division of Penguin Random House，first were reported by Britain's Daily Telegraph newspaper.
The changes to Dahl's books mark the latest debate over cultural sensitivity.Those who support updates seek to protect young people from cultural，ethnic and gender stereotypes in literature and other media.Critics complain that revisions to suit 21st century sensibilities risk weakening the genius of great artists and preventing readers from facing the world as it is.
The Roald Dahl Story Company controls the rights to the books.The company said it worked with Puffin Books to review the texts because it wanted to ensure that"Dahl's wonderful stories and characters continue to be enjoyed by all children today."
Inclusive Minds，a group that is working to make children's literature more inclusive and accessible，reviewed the language in a partnership effort with Puffin Books.Inclusive language avoids terms that could be seen as excluding specific groups of people.Any changes were"small and carefully considered，"the company said.
"When publishing new print runs of books written years ago，it's not unusual to review the language used alongside updating other details，including a book's cover and page layout，"the company said their guiding principle throughout had been to maintain the storylines，characters，and the spirit of the original text.
PEN America，a community of some 7，500 writers that advocates for freedom of expression，said it was"alarmed"by reports of the changes to Dahl's books.Suzanne Nossel，chief executive of PEN America，commented on Twitter.She said if we try"to correct for sensing slights （怠慢） instead of allowing readers to receive and react to books as written，we risk distorting the work of great authors and clouding the essential lens （透鏡） that literature offers on society."
Laura Hackett is a childhood Dahl fan who is now deputy literary editor of London，England's Sunday Times newspaper.She had a more personal reaction to the news."The editors at Puffin should be ashamed of the botched surgery they've carried out on some of the finest children's literature in Britain，"she wrote."As for me，I'll be carefully putting away my old，original copies of Dahl's stories，so that one day my children can enjoy them in their full，nasty and colorful glory."
（1）What is the reason for the changes to Dahl's books？
A．To make Dahl's books more enjoyable.
B．To review the language used and add details.
C．To remove words that show disrespect to some people.
D．To keep the storylines，characters，and the spirit of the original text.
（2）What might the underlined word in Paragraph 6 probably mean？
A．Preventing.
B．Appreciating.
C．Understanding.
D．Misrepresenting.
（3）Which of the following may Laura Hackett agree？
A．The new version of the books is worth collecting.
B．The original version of the books are more valuable.
C．The original books weaken the genius of great artists.
D．The new version allows readers to receive books as written.
（4）What might be the proper title of the passage？
A．New Changes to Roald Dahl Books Start Argument
B．Different Opinions on New Editions of Classic Books
C．Authors or Publishers both Control the Right to Books
D．New Editions of Roald Dahl's Classic Books Available
（5）What is the purpose of the passage？
A．To persuade readers to buy Roald Dahl's classic books.
B．To entertain readers by the changes of Roald Dahl's books.
C．To recommend the new version of Roald Dahl's classic books.
D．To inform diverse views on the changes of Roald DahI's books.發(fā)布：2025/1/30 8:0:1組卷：1引用：1難度：0.4