How does an ecosystem (生态系统) work? What makes the populations of different species the way they are? Why are there so many flies and so few wolves? To find an answer, scientists have built mathematical models of food webs, noting who eats whom and how much each one eats.
With such models, scientists have found out some key principles operating in food webs. Most food webs, for instance, consist of many weak links rather than a few strong ones. When a predator (掠食动物) always eats huge numbers of a single prey (猎物), the two species are strongly linked; when a predator lives on various species, they are weakly linked. Food webs may be dominated by many weak links because that arrangement is more stable over the long term. If a predator can eat several species, it can survive the extinction (灭绝) of one of them. And if a predator can move on to another species that is easier to find when a prey species becomes rare, the switch allows the original prey to recover. The weak links may thus keep species from driving one another to extinction.
Mathematical models have also revealed that food webs may be unstable, where small changes of top predators can lead to big effects throughout entire ecosystems. In the 1960s, scientists proposed that predators at the top of a food web had a surprising amount of control over the size of populations of other species—including species they did not directly attack.
And unplanned human activities have proved the idea of top-down control by top predators to be true. In the ocean, we fished for top predators such as cod on an industrial scale, while on land, we killed off large predators such as wolves. These actions have greatly affected the ecological balance.
Scientists have built an early-warning system based on mathematical models. Ideally, the system would tell us when to adapt human activities that are pushing an ecosystem toward a breakdown or would even allow us to pull an ecosystem back from the borderline. Prevention is key, which scientists says because once ecosystems pass their tipping point (临界点), it is remarkably difficult for them to return.
1. What have scientists discovered with the help of mathematical models of food webs?| A．The living habits of species in food webs. |
| B．The rules governing food webs of the ecosystems. |
| C．The approaches to studying the species in the ecosystems. |
| D．The differences between weak and strong links in food webs. |
| A．has a wide food choice | B．can easily find new prey |
| C．sticks to one prey species | D．can quickly move to another place |
| A．The prey species they directly attack will die out. |
| B．The species they indirectly attack will turn into top predators. |
| C．The living environment of other species will remain unchanged. |
| D．The populations of other species will experience unexpected changes. |
| A．By getting illegal practices under control. |
| B．By stopping us from killing large predators. |
| C．By bringing the broken-down ecosystems back to normal. |
| D．By signaling the urgent need for taking preventive action. |
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【推荐1】Mr. Watson is late again. He has no time for breakfast. But at least he has the basic necessities: bang on the minute, the coffee machine supplies his first hot drink. The motion sensor is activated and notifies the garage door, which now opens. In all the rush, he has forgotten to switch off the iron and light. No problem. He deals with that while underway via his smartphone.
What Mr. Watson benefits from is the idea of Smart Home, an idea more topical and attractive than ever. But what does “Smart Home” mean? “Smart Home” is an indicator of the use of technical systems, automated processes and connected, remote-controlled devices in apartments and houses. The main objective of the functions is to improve the quality of life and convenience in the home. Other goals are greater security and more efficient use of energy thanks to connected, remote-controllable devices.
“Smart Home” was brought to life through continuous technological progress, in particular through the Internet and computer. Science fiction literature in the 1950s described the first visions of homes that were monitored and controlled fully automatically by machines. The 1999 Disney film “Smart House” was about household computers and the consequences when smart machines took on a life of their own. The Fraunhofer inHaus Center, which was opened in Duisburg in 2001, was a lighthouse project which involved exploring and testing new system solutions in a residential environment. The first T-Com House from Deutsche Telekom in Berlin was opened to interested visitors in 2005. The focus of this model project was on connecting various home appliances and controlling them by means of different input devices.
Scientists have already been working for decades of years on “Smart Home”. There are still challenges as a result of trends like an aging society, greater environmental awareness and the related wish for a sustainable energy supply. But there are more solutions. What is the next big evolutionary advance?
1. How does the author introduce the topic in Paragraph 1?| A．By giving a definition. | B．By describing a scene. |
| C．By making a prediction. | D．By providing evidence. |
| A．It is a newly-formed concept. |
| B．It involves energy-consuming devices. |
| C．It values security more than efficiency. |
| D．It’s not all about comfort and convenience. |
| A．Smart Home has changed people’s life a lot. |
| B．Smart Home is equipped with advanced devices. |
| C．Smart Home develops with technological advances. |
| D．Smart Home is favored by more than one generation. |
| A．Concerned. | B．Doubtful. | C．Cautious. | D．Hopeful. |
Instead of satellites, Locata uses ground-based equipment to send a radio signal over a localized area that is a million times stronger on arrival than GPS. It can work indoors as well as outdoors, and the makers claim that the receivers can be shrunk(缩小) to fit inside a regular cell phone. Even the US armies, which invented GPS technology, signed a file last month agreeing to a test of Locata at the White Sands Missile Range in New Mexico.
“This is one of the most important technology developments for the future of the positioning industry,” says Nunzio Gambale, CEO and co-founder of the firm Locata, based in Griffith, Australia.
As for the Locata’s correctness, Christopher Morin of the US Air Force tested it recently at White Sands, and it worked to within 18cm along any axis(轴). Morin said it should be possible to get the exactitude down to 5cm.
The tests were performed in an open desert where GPS also worked beautifully, but its signal was weak—like a car headlight from 20,000 kilometers away—and easily cut off by solid objects(实心的物体). Locata’s signal was far stronger, though not guaranteed to work in a complex urban environment, said David, speaker of the UK’ s General Lighthouse Authorities.
Locata’s technology will face competition in the race to transform indoor navigation. But it could shine in specific areas, Gambale said. Robots with Locata could easily navigate inside buildings without the complex optical(视觉的) systems they need at the moment. And the process that handles correct location data could not only guide you around a mall, railway station or airport, but also take you to the exact shelf in a shop for the product you want. It would be small and cheap enough for smart phones and it should be available within five years—a similar path to the one GPS took on its way towards the world, he said.
1. The passage is written mainly to ______.
| A．encourage people to buy the Locata |
| B．tell us the disadvantages of the GPS |
| C．introduce a new positioning system Locata |
| D．tell us that Locata will replace GPS one day |
| A．Without the help of the satellites, Locata can tell you where you are. |
| B．Locata will be popular with most people even including the US armies. |
| C．Locata has a better signal than GPS in some bad environments. |
| D．In five years, Locata will take the place of GPS. |
| A．did the experiment at White Sands last month |
| B．believed the Locata would help to develop smart robots’ creation |
| C．doubted whether Locata can work in a complex environment or not |
| D．was worried about the competition the Locata faced |
| A．Accuracy. | B．Speed. |
| C．Determination | D．Length |
| A．Locata is as small as a cell phone. |
| B．GPS is the most practical position system at present. |
| C．Locata will tell you how to get what you want in the future. |
| D．Locata will enter our lives through the cell phone, just like GPS. |
【推荐3】When you picture doing a science project, you might imagine looking through a microscope or building a model volcano. But science projects can be done anywhere. Many teens get inspired from playing musical instruments to doing gymnastics. All it takes to transform your favorite activities into a science project is identifying a problem you want to solve.
Elizabeth, 14, who is in seventh grade at Davis Drive Middle School in Cary, N. C, designed a program. Her method is based on the golden ratio (比例). This ratio is often used to create pleasing parts in artworks. The ratio also appears in nature. Elizabeth’s data storage strategy helps computers write data evenly (均匀地) across memory devices. This could help such devices last longer.
“As long as I can remember, I’ve been an artistic person,” Elizabeth says, “In fourth grade, my art teacher taught us about the golden ratio. And at that point it was just, you know, something to use when we were painting.” But last year, Elizabeth had to replace the memory in her own computer, thinking the golden ratio might work in information storage, too. Elizabeth tested her golden-ratio technique by running programs on a computer.
But before this project, Elizabeth had no coding experience. To prepare, she spent months reading a textbook on how to code. She says, “It wasn’t like an ‘ah-ha’ moment. Writing programs is such a boring process. But it was just exciting to explore and see the computer actually just doing stuff that I told it to do after those hours.”
“Don’t limit yourself,” Elizabeth adds, “One of the biggest challenges you face is changing your mindset. I never thought that science or computer science would be my kind of thing, but after learning a bit about programming, I found that it was actually a new way to express myself. Words, painting, now programming.”
1. What can we learn about science projects according to this passage?| A．They can come from different hobbies. | B．They will inspire teens to find solutions. |
| C．They need skills in building models. | D．They may involve great imagination. |
| A．Strengthening memories. | B．Storing information. |
| C．Creating fine works. | D．Protecting nature. |
| A．Imagination is the source of creation. | B．Laugh it off when facing difficulties. |
| C．Well begun is half done. | D．Every effort will pay off. |
| A．Expressing doubts. | B．Making promises. |
| C．Offering advice. | D．Giving response. |
Is traffic a big problem where you live? Increased cycling may be the answer. Where are the best places to live and cycle? A new report lists the best bike-friendly cities around the world.
Top of the list is Amsterdam, the bike capital of the world. An unbelievable 40% of all traffic movements are by bicycle. Copenhagen, the city of bikes, is a city where 32 % of workers cycle to work because it's fast and easy. Berlin is another European city that's great for cycling. The city has about 80 kilometers of bike lanes, and 50 kilometers of pavement (人行道)paths. Cycling accounts for 12% of total street traffic.
Barcelona has been praised for its cycle service ''Bicing''，a bicycle service that allows users to take and leave bicycles at any of the 100 stations spread around the city. The city has created a ''green ring'' that surrounds the city area of Barcelona with a bike path. There are 3,250 parking spaces for bikes at street level at present. Barcelona City is also building a new underground car park for bicycles.
The UK has its cycle-friendly cities too. Bristol is the birthplace of ''Sustrans'' — the cycle-route charity which was formed 30 years ago. One of their projects was turning an old rail line between Bristol and Bath into a bike route. Other bike-friendly cities in the UK include Cambridge and York.
Bicycle is a most popular means of transportation in China. Nowadays, riding a bicycle is also a good way to support low-carbon living. There are many riding routes in Beijing for outdoor-lovers to explore. Cyclists can get close enough to experience the history and culture of Beijing, including the Forbidden City, the Bird's Nest, Hutong etc.
1. Why do 32% of workers cycle to work in Copenhagen?(不多于六个单词)2. What is "Sustrans'' ？(不多于三个单词)
3. What is also a good way to support low-carbon living nowadays?(不多于三个单词)
4. What is the passage mainly about?(不多于七个单词)
【推荐2】Prince William, second in line to the British throne, gave his first TED Talk on Saturday to launch his Earthshot Prize, a competition that will award five £ 1 million prize money every year for the next decade to those who can come up with solutions to environmental problems.
Any person, group or organization around the world is qualified, and any suggestion is welcome, so long as it is applicable globally. It could be a new technology, a new approach, a new governmental policy or any other ideas toward five environmental goals -fixing the climate, purifying the air, protecting nature, cleaning oceans and handling waste.
"Earthshot" was inspired by John F. Kennedy's "Moonshot," an ambitious 1961 mission to get a man on the moon within a decade. The purpose of the prize is partly to arouse excitement and offer what Prince William called “a bit of catalyst, a bit of hope, a bit of positivity" at a time when the world needs. The money will come from donors around the world. The prize committee includes many celebrities.
Prince William has environmental activism in his blue blood. Both his grandfather, and his father Prince Charles were active environmentalists. Prince William acknowledged his heritage by saying he had always listened, learned and believed what they were saying about the environment. Besides speaking wise words, he also puts forward a good prize. Over a million pounds is significantly more than a Nobel Prize and should inspire some serious and creative thinking about the difficulties of Planet Earth. Unlike the Nobel Prize money, the Earthshot money is supposed to be spent on the winning project. “If we achieve these goals, by 2030 our lives won't be worse, and we won't have to sacrifice everything we enjoy. Instead, the way we live will be healthier, cleaner, smarter, and better for all of us," he said.
1. What can be learned about The Earth shot Prize?| A．It will be awarded to Britons. |
| B．It aims to solve social problems. |
| C．It is named after a moon mission. |
| D．It offers £ 50 million in total. |
| A．a method to monitor sea levels |
| B．a new technology to forecast the weather |
| C．a new approach to recycling the waste |
| D．a local government policy to ban fishing |
| A．Encouragement. | B．Alarm. | C．Challenge. | D．Surprise. |
| A．Earthshot Prize equals Nobel Prize. |
| B．Planet Earth will be cleaned by 2030. |
| C．Prince William only talks the talk. |
| D．Prince William is influenced by his family. |
【推荐3】If 2021 was the wake up call, then 2022 is the year of taking the urgent action needed to deal with climate change.
Activists and campaigners everywhere continue to be frustrated（使... 沮丧）by the lack of action from world leaders and corporations.
1. Support Sustainable（可持续的）Fashion
The fashion industry is one of the biggest contributors to pollution, making up 20% of global industrial water pollution, as well as being a major contributor to greenhouse gas emissions（排放）—according to the World Economic Forum, it produces 10% of all humanity's carbon emissions, as well as being the second-largest user of the world's water supply.
Sustainable fashion, meanwhile, is clothing that is made from environmentally-friendly materials.
2. Make an Event Out of Planting Trees
A fully-grown tree absorbs 48 pounds of carbon dioxide per year. Trees contribute much to cleaning the air.
3. Follow a More Plant-Based Diet
Going plant-based is a fashion that has really picked up over the last few years, and one of the simplest ways you can help deal with climate change this year is by following a more plant-based diet, or making plant-based choices. Research shows that a global shift to a more plant-based diet could reduce the emissions of greenhouse gases by 70% by 2050.
| A．They are also a great way to prevent flooding. |
| B．These trees form a natural protection from the sun. |
| C．Besides, it is also a healthier alternative for your body. |
| D．As a result, meat and milk products demand more resources. |
| E．We can do our part in daily life to cut our own carbon footprints, though. |
| F．It is harmless in the making process, and uses natural resources responsibly. |
| G．The past year has witnessed extreme weather events and rapidly changing weather pattern |
【推荐1】It’s not easy being a teenager-nor is it easy being the parent of a teenager. You can make your child feel angry, hurt, or misunderstood by what you say without realizing it yourself. It is important to give your child the space he needs to grow while gently letting him know that you will still be there for him when he needs you.
Expect a lot from your child, just not everything. Except for health and safety problems, such as drug use or careless driving, consider everything else open to discussion. If your child is unwilling to discuss something, don’t insist that he tell you what’s on his mind. The more you insist, the more likely that he’ll clam up. Instead, let him attempt to solve things by himself. At the same time, remind him that you’re always there for him if he should seek advice or help. Show respect for your teenager’s privacy. Never read his mail or listen in on personal conversations.
Teach your teenager that the family phone is for the whole family. If your child talks on the family’s telephone for too long, tell him he can talk for 15 minutes, but then he must stay off the phone for at least an equal period of time. This not only frees up the line so that other family members can make and receive calls, but teaches your teenager moderation (节制). Or if you are open to the idea, allow your teenager to have his own phone that he pays for with his own pocket money or a part-time job.
1. The main purpose of the text is to tell parents ________.| A．how to look after a teenager | B．how to help a teenager grow up |
| C．how to control a teenager | D．how to respect a teenager |
| A．Become excited. | B．Show respect. |
| C．Seek help. | D．Refuse to talk. |
| A．Give him advice only when necessary. |
| B．Not allow him to learn driving or take drugs. |
| C．Let him have his own telephone unconditionally (无条件地). |
| D．Never talk about personal things with him. |
Password management firm SplashData released its list of the worst passwords of the year and it's just as terrible as you'd think. The most common leaked password in 2014 was "123456," followed by "password" — both topped the list the year before, too.
While numbers were as popular as ever as passwords, sports terms like “baseball" and "football" were used more often. Birthday years were common too (especially 1989, 1990, 1991 and 1992) and names like "Michael", "Jennifer" and "Hunter" are also among the top 100 worst passwords of 2014.
Here's a look at the top 10 worst passwords of the year:
1. 123456 (Unchanged from 2013) 6. 234567890 (Unchanged)
2. password (Unchanged) 7. baseball (New)
3. 12345 (Up 17) 8. dragon (New)
4. 12345678 (Down 1) 9. football (New)
5. qwerty (Down 1) 10. monkey (New)
This year's worst passwords are painfully weak, but what were once considered clever password strategies — using symbols, capitalizations, the number 3 in place of the letter "e" — are old tricks.
It's now recommended to pick a different password for each account you use — you wouldn't use the same key in all of your locks, and the same goes for passwords.
Companies like Facebook, Twitter and Apple are now trying to make hacking more difficult on their services by offering two-factor authentication (认证), which is basically like double locking your door at night. Each time you want to log into (登录) that account, the company will send a code to your phone — it changes after each login attempt, so hackers would have to be in physical possession of your smartphone to know the code.
1. What can we learn from the text?
| A．Hackers leaked many more passwords in 2014. |
| B．Symbols were among the top 10 worst passwords. |
| C．123456 was the most common leaked password in both 2013 and 2014. |
| D．People are getting more experienced in picking their passwords. |
| A．One. | B．Two. | C．Three. | D．Four. |
| A．Using long and strange passwords. |
| B．Changing passwords regularly. |
| C．Replacing "e" by "3" when setting passwords. |
| D．Choosing different passwords for different accounts. |
| A．don't accept weak passwords |
| B．double lock their doors at night |
| C．combine the password with a code to prove one's identity |
| D．prevent hackers from stealing customers' smartphones |
【推荐3】As US firm launched (发行) a “smart lock” that can let you into your home using a mobile phone and you don’t even need to take the phone out of your pocket to open the door. The August lock costs $249 and can even be set to automatically let in friends or workmen.
August was created by technology entrepreneur (企业家)Jason Johnson and industrial designer Yves Behar, and the product will finally go on sale in Apple Stores this week. It is made of “durable anodized aluminum”and can be started and managed using a mobile app and online. It is connected to the existing door lock and is battery operated.
To open the lock, anyone with a code can approach the door, enable their phones’ Bluetooth and press the relevant (相关的))address from the app. The lock takes a few seconds to scan and confirm the visitors’ identity. Once the identity is confirmed, the circle of red dots on the front of the device turns green and the August lock twists (转动)to open the door.
The makers claim that it takes just 10 minutes to install. To allow keyless access to friends, family and other visitors, the homeowner must send them an invitation. This can be done using existing contacts from the homeowner’s phone’s address book, but other persons must have the August app to receive the unique code of the lock from the homeowner.
When someone enters the house, the homeowner is sent a push notice. Another notice is sent when the person leaves. This means homeowners can keep track of how long cleaners or builders spend in the house and every visitor’s details and visiting information is stored on a Log.
1. Who are not allowed to enter the house with the August lock?| A．Family. | B．Friends. | C．Strangers. | D．Workmen. |
| A．By the August app. | B．By receiving a call. |
| C．By the address book. | D．By asking the entrepreneur. |
| A．One | B．Two | C．Three | D．Four |
| A．How to Invite a Friend. |
| B．How to Unlock a House. |
| C．August-the Best Lock. |
| D．August-a Smart Lock. |
