1 . Beneficial algae (藻类) help feed the corals and give them their color. But higher-than-normal ocean temperatures can cause some corals to bleach (白化), which means they lose those helpful algae. Affected corals can become bone-white and may struggle to survive. But when they bleach, some corals turn from red to blue to purple.
According to a new study, those flashy colors may help corals win back their lost algae partners and this can help the corals recover from bleaching.
Elena Bollati, a biologist who carried out the study, turned to experiments to see what conditions cause “colorful bleaching”.
In the lab, she put corals to a slow rise in temperature. As the team turned up the heat, the amount of algae dropped. They also saw a red-colored fluorescence (荧光) the algae gave out when lit with certain wavelengths. A few weeks after the heat stress, this red fluorescence jumped. The team also monitored fluorescence from the coral itself. That light is caused by the pigment (色素) that gives the corals color. The scientists also found that an imbalance of certain nutrients could lead to colorful bleaching.
Healthy, unbleached corals rely on their algae to absorb some sunlight. The algae uses some of this light to make food for the coral. It also helps screen the corals from some of that sunlight. After losing those algae, the corals face exposure to more sunlight. That light — including its blue wavelengths — can enter and bounce around inside the corals. Those reflections boost the coral tissue’s exposure to the blue light, thus making the bleached corals pump out more pigments.
Like the pigments that color skin, coral pigments are protective. They act like a sunscreen. By bumping up pigment production, the corals may be making a friendlier home for returning algae. The team also observed that vividly colored areas of the corals more quickly regained their algae than areas with less pigment.
1. What is the purpose of the experiment in the text?| A．To prove the harmful effect of bleaching. |
| B．To look for effective ways to study corals. |
| C．To show the important effect of pigment on corals. |
| D．To find out the reason for bleaching corals changing colors. |
| A．The pigments. | B．The heat. |
| C．Sunlight. | D．The nutrients. |
| A．The coral. | B．The algae. | C．The food. | D．The light. |
| A．More Corals Are Suffering From Bleaching |
| B．High Temperatures Is Causing Corals to Bleach |
| C．Going Colorful May Be Corals’ Fight Against Bleaching |
| D．Bleaching Is Making Corals Disappear From the Earth |
2 . Until recently, several lines of evidence—from fossils, genetics, and archaeology—suggested that humans first moved from Africa into Eurasia (the land of Europe and Asia) about 60,000 years ago, quickly replacing other early human species, such as Neanderthals and Denisovans, that they may have met along the way.
However, a series of recent discoveries, including 100,000-year-old human teeth found in a cave in China, have clouded this straightforward statement. And the latest find, a prehistoric jawbone at the Misliya Cave in Israel dating back to nearly 200,000 years ago, which is almost twice as old as any Homo sapiens(智人) remains discovered outside Africa, where our species was thought to have originated from, has added a new and unexpected twist.
The find suggests that there were multiple waves of migration across Europe and Asia and could also mean that modern humans in the Middle East were interacting, and possibly mating, with other human species for tens of thousands of years. “Misliya breaks the mould (模式) of existing assumptions of the timing of the first known Homo sapiens in these regions,” said Chris Stringer, head of human origins at the Natural History Museum in London. “It’s important in removing a long-lasting constraint(限制) on our thinking.”
Prof. Hershkovitz, who led the work at Tel Aviv University said, “What Misliya tells us is that modern humans left Africa not 100,000 years ago, but 200,000 years ago. This is a revolution in the way we understand the evolution of our own species.” He also added that the record now indicates that humans probably travelled beyond the African continent whenever the climate allowed it. “I don’t believe there was one big departure from Africa,” he said. “I think that throughout hundreds of thousands of years humans were coming in and out of Africa all the time.”
The discovery means that modern humans were potentially meeting and interacting during a longer period with other ancient human groups, providing more opportunity for cultural and biological exchanges. It also raises interesting questions about the fate of the earliest modern human pioneers. Genetic data from modern-day populations around the world strongly suggest that everyone outside Africa can trace their ancestors back to a group that left around 60,000 years ago. So the inhabitants of the Misliya Cave are probably not the ancestors of anyone alive today, and scientists can only guess why their branch of the family tree came to an end.
1. What does the Misliya discovery suggest?| A．Our ancestors were powerful and kind of agreesive. |
| B．Our ancestors left Africa much earlier than thought. |
| C．The origins of modern humans are from Europe. |
| D．Homo sapiens, Neanderthals and Denisovans once lived together. |
| A．Early human species living in Europe |
| B．Neanderthals and Denisovans. |
| C．People first moving from Africa into Eurasia. |
| D．Ancient people living in Africa all the time. |
| A．Climate was a big factor in human migration from Africa. |
| B．There was a large-scale human migration from Africa. |
| C．Human migration was occasional in Africa 200,000 years ago. |
| D．The Misliya find is against our understanding of human evolution. |
| A．They were ancestors of people living in China. |
| B．They left evidence for their mysterious disappearance in history. |
| C．They probably contributed little to present-day people genetically. |
| D．They could be traced by their remains left on their travelling route. |
3 . In the first days after a team of 25 delivery robots landed on George Mason University's campus in January,they appeared to cause curious glances and many photos but not much else.
It was clear,officials said,that more time and more data would be necessary to understand whether the robots would change the campus culture or become forgettable.Two months later,an extra 1,500 breakfast orders have been delivered autonomously,according to the technologists of Sodexo,a company that manages food service for GMU and works closely with the robots.
Research has shown that up to 88 percent of college students skip breakfast,primarily because of lack of time,but that number is starting to turn around when delivery robots arrive on campus.They're constantly seen making the 15 minute trip from campus restaurant to a handful of nearby dorms,as well as to other buildings across campus,where students meet them.Two months later,breakfast has replaced dinner as the go-to meal for robot delivery.
Sodexo officials have noted that college students are main users of food delivery apps and place a high value on convenience and multiple options when they dine.During the morning hours,restaurant experts say,there is generally more emphasis（强调）on speed than any other part of the day.Combine college students'love of food delivery with messy morning routines,and perhaps they have a perfect recipe for robots to deliver in the campus.
The robots also provide campus officials with valuable data showing how meal plans are being used,which could lead to changes in how the university serves students over time.Sodexo technologists also announced Monday that a new team of more than 30 robots is launching at Northern Arizona University
.
| A．They are on diets. |
| B．They have a tight schedule. |
| C．The food doesn't agree with them. |
| D．GMU doesn't offer delivery services. |
| A．College students. | B．Campus officials. |
| C．College professors. | D．Restaurant managers. |
| A．They make timely deliveries. |
| B．They were ignored at first. |
| C．They mainly carry dinner at present. |
| D．They have changed the whole campus culture. |
| A．Delivery services grow fast in college. |
| B．Breakfast in necessary for college students. |
| C．Robots help with GMU's campus management. |
| D．Delivery robots are changing students'eating habits. |
4 . We all love to take photographs. It's a simple way to snap a special moment, an amazing view, or just to show off your artistic skills. And it's great to look back through your photo albums and share memories with your friends. In fact, they show a snapshot（快照）in time. This hasn't really changed since the invention of photography in the 1830s. But one thing that has changed is the equipment we use.
For many years, we have used traditional cameras to take our pictures with. Our images were taken onto camera film which was then processed into negatives from which photos were printed— a lengthy process. And we've had a range of cameras to choose from— from the simple compact camera to more advanced single lens reflex, or SLR cameras.
But the biggest change has come with the development of digital devices. This has made taking photo quicker and easier. It's enabled us to take a snap and review our pictures instantly. We've been able to deal with them in post-production, using software on our computer. And of course, we've been able to share them like never before— particularly on social media.
Of course, now we have the smartphone— a phone that is, well, smart because it can take photos and sometimes very good quality ones, and we can share them easily. So does that mean the traditional camera will eventually become outdated? Figures from Japan show how the market is shrinking: shipments of compact digital cameras from companies like Olympus, Canon and Nikon were down 39 percent year on year.
But Phil Hall, editor of Tech Radar magazine, told the BBC that while people are swapping their compact cameras for smartphones, "manufacturers are looking at the more higher-end cameras, high-end compacts, DSLRs, which are the ones you can attach lenses to, mirrorless cameras. In this sense, there's nothing to worry about."
1. What does the underlined word "they" in Paragraph I refer to?| A．Private memories. | B．Photo albums |
| C．Artistic skills. | D．Photographs |
| A．Instant access to taking photographs. | B．Sharing moments on social media. |
| C．The development of digital technology. | D．Post-production of software on computer. |
| A．Optimistic. | B．Negative. | C．Worried. | D．Uncertain. |
| A．What a dilemma for cameras! | B．What can smartphones do for us? |
| C．Are smartphones killing cameras? | D．Camera producers survive the hard times |
5 . The Israeli farmers who pioneered the revolutionary technology known as drip irrigation（滴流灌溉） weren’t trying to solve one of the world’s most urgent problems. They were just trying to survive. They lived in the desert, and they didn’t have enough water to grow their crops.
In its simplest form, it was little more than a pipe with holes in it. But behind each hole was a hi-tech dripper that let out just the right amount of water. Snaked along a row of crops so that the holes were positioned directly above the roots, the pipe could direct each precious drop of water directly to the plants, getting a bigger harvest while using a very small amount of water.
Over time, the farmers improved upon the technology, perfecting the drippers that regulated the flow of water, and connecting the pipelines to computers that could determine exactly how much water each plant needed and when.
If the global population kept growing, the rest of the world would increasingly resemble their little community in the desert. So they began selling their irrigation systems in other parts of the world, eventually expanding to more than 110 countries. Netafirm, the company says it’s lifting people out of poverty and conserving water at a time when the importance of doing so has never been clearer.
The mass adoption of drip irrigation won’t save the world by itself. To avoid the coming catastrophe, nearly everybody will, in some way, have to do more with less, perhaps through accepting and using other new technologies. Otherwise, it’s going to get ugly.
1. Why is drip irrigation called “the revolutionary technology”?| A．It saves the world all by itself. |
| B．It is controlled by computers. |
| C．It makes irrigation more effective. |
| D．It provides deserts with water. |
| A．Lacking water. | B．Lacking labor. |
| C．Lacking food. | D．Lacking energy. |
| A．By drilling holes on the pipes. |
| B．By regulating water via drippers. |
| C．By snaking pipes along the crops. |
| D．By placing pipes just above roots. |
| A．Less water; More harvest. |
| B．New technology; New world. |
| C．More grain; Less starvation. |
| D．Water saving; World surviving. |
6 . Do you want to live another 100 years or more? Some experts say that scientific advances will one day enable humans to last tens of years beyond what is now seen as the natural limit of the human life span.
“I think we are knocking at the door of immortality(永生),” said Michael Zey, a Montclair State University business professor and author of two books on the future. “I think by 2075 we will see it and that’s a conservative estimate(保守的估计).”
At the conference in San Francisco, Donald Louria, a professor at New Jersey Medical School in Newark said advances in using genes as well as nanotechnology(纳米技术) make it likely that humans will live in the future beyond what was possible in the past. “There is a great effort so that people can live from 120 to 180 years,” he said. “Some have suggested that there is no limit and that people could live to 200 or 300 or 500 years.”
However, many scientists who specialize in aging are doubtful about it and say the human body is just not designed to last past about 120 years. Even with healthier lifestyles and less disease, they say failure of the brain and organs will finally lead all humans to death.
Scientists also differ on what kind of life the super aged might live. “It remains to be seen if you pass 120, you know; could you be healthy enough to have good quality of life?” said Leonard Poon, director of the University of Georgia Gerontology Centre. “At present people who could get to that point are not in good health at all.”
1. By saying“we are knocking at the door of immortality”,Michael Zey means_________.| A．they have got some ideas about living forever |
| B．they believe that there is no limit of living |
| C．they are able to make people live past the present life span |
| D．they are sure to find the truth about long living |
| A．the human body is designed to last past about 120 years |
| B．it is possible for humans to live longer in the future |
| C．it is still doubtful how long humans can live |
| D．people can live from 120 to 180 |
| A．a great effort |
| B．the conservative estimate |
| C．the idea of living from 200 to 300 years |
| D．the idea of living beyond the present life span |
| A．No Limit for Human Life |
| B．Living Longer or not |
| C．Science,Technology and Long Living |
| D．Healthy Lifestyle and Long Living |
7 . At 12 years old, Braeden Mannering is already well on his way to running an empire! A 2016 win of Delaware's Healthy Lunchtime Challenge brought Braeden to the White House, where the president asked the children at the event to think about how they could pay the experience forward.
A few days later, on the drive back home, Braeden saw a homeless man in the rain. He had his parents stop so that he cold give the man a bag of snacks. Braeden knew at that moment that this was how he wanted to pay it forward. He knew what he wanted to do in the future. He felt that it was his duty to help people in trouble.
Since that day in July,2016,Braeden has handed out over 8,000 bags to the homeless through his organization Brae's Brown Bags, also known as 3B.These bags vary (各不相同) in contents, and include food, toiletries (化妆品) and even books for the kids 'bags.
In addition to packing and distributing (分发) bags, Braeden travels the country, giving talks in schools to inspire other young people to help their communities. On his travel, he's raised$60,000 to expand his program. He also is a leader at the annual Delaware Hunger Conference, where he encourages kids to write to lawmakers and help pack bags, showing them how to make a difference.
This is a huge accomplishment, especially for someone of his age. But, as he says, “Anyone can change the world, as long as you dream big."
1. What does the underlined word "it" in Para.2 refer to?| A．The bag. | B．The experience. |
| C．The event. | D．The moment. |
| A．Provide children with clothes. |
| B．Help homeless women with make-up. |
| C．Hand out bags for people to do shopping. |
| D．Donate things in bags to people losing their homes. |
| A．To raise some money. |
| B．To give talks in schools. |
| C．To pay a visit to some lawmakers. |
| D．To inspire young people to help their communities. |
| A．It is great considering his young age. |
| B．It is not a little boy's task to do so. |
| C．The government should give him more help. |
| D．He sets a good example for other children. |
8 . People spend about a third of their life sleeping and cannot survive without it. But while scientists have long understood the importance of getting enough sleep, the key part played by light exposure can sometimes be overlooked (忽视). The reason why light is so important is that it sets our body clock, through specialized light sensors within the eye. Our eye detects the light and dark cycle within our environment and adjusts the body clock so that the inner and outer day coincide (相符). This is so powerful that people who have eye damage can find their body clock is thrown off, leading to sleep problems.
Without any access to light, the human body clock appears to change, adding about half an hour on to its 24-hour cycle for each day of darkness. Jet lag (飞行时差反应) is the most obvious example of the effect light can have. Exposure to light in the new time zone helps reset our body clock to local time, telling us the right time to sleep.
In 1800, most people across the world worked outside and were exposed to the change from day to night. Today, many of us miss out on the natural environment as we mostly work inside. We have become a light-deprived (光照不足的) species, and this has far-reaching consequences for the quality of our sleep, and consequently our well-being. The proper amount varies from person to person, but we do know that our bodies need exposure to very bright light that most indoor lighting does not provide. One notable side effect is Seasonal Affective Disorder (SAD), a form of depression thought to affect 2-8% of Europeans, which is linked to lack of sunlight exposure.
Research in this area could help people make informed choices. Simply by reducing light exposure before going to bed, and trying to get as much morning light as possible, they could improve their sleep and well-being.
1. What does the underlined part “it” in the first paragraph refer to?| A．The sensor. | B．Sleep. |
| C．Light. | D．The eye. |
| A．To show people in different time zones have different sleep patterns. |
| B．To advise frequent fliers to get plenty of sun to avoid discomfort. |
| C．To prove irregular light and dark cycles affect our body clock. |
| D．To explain why our body clock has a 24-hour cycle. |
| A．It comes along with cold temperatures. | B．It results from a lack of natural light. |
| C．It affects people living on islands. | D．It happens mainly in summer. |
| A．Early to bed and early to rise makes a man healthy. |
| B．Natural light is the key to a good night’s sleep. |
| C．Our body clock is linked to the mood disorder. |
| D．Life is really hard for nightbirds. |
9 . Your morning can determine the rest of your workday. It’s no wonder that so many successful business people keep strict morning habits. If you want to do your best work and be a more productive person, try to follow these four common morning habits.
Wake up early
Successful business people wake up early. Early risers have many advantages. They tend to delay（拖延） less compared with people who stay up late at night. They are also less stressed because, instead of rushing out the door, they take time for themselves and prepare for their day.
Get moving
Successful business people attach importance to their health. After all, a healthy body and mind go together. Morning exercise appears to be best for reducing stress by lowering blood pressure. It also helps you burn more fat throughout the day and lose weight.
Recharge your motivation（动力）
Successful business people understand that motivation doesn’t last forever and needs to be constantly recharged. Reading encouraging sayings is a good way. Thinking about where you are and where you want to go can help you focus on your larger goals.
Eat your frog
Mark Twain once said, “Eat a live frog first thing in the morning, and nothing worse will happen to you the rest of the day.” In other words, handle your day’s hardest job early when your mental energy is at its highest. Choose only one “frog” of the day and complete it before your normal workday begins.
1. The writer got his ideas by studying many ________.| A．employees | B．novelists |
| C．sports athletes | D．business people |
| A．Reduce stress. | B．Increase weight. |
| C．Reduce delays. | D．Increase blood pressure. |
| A．By staying up late. | B．By reading encouraging sayings. |
| C．By burning more fat. | D．By eating heavily in the morning. |
| A．Alive animal. | B．A life goal. |
| C．A normal weekday. | D．A hard job. |
| A．Morning habits. | B．Business advantages. |
| C．Healthy diets. | D．Office tips. |
10 . Technology offers conveniences such as opening the garage door from your car or changing the television station without touching the TV.
Now one American company is offering its employees a new convenience: a microchip implanted (植入) in their hands. Employees who have these chips can do all kinds of things just by waving their hands. Three Square Market is offering to implant microchips in all of their employees for free. Each chip costs $300 and Three Square Market will pay for the chip. Employees can volunteer to have the chips implanted in their hands. About 50 out of 80 employees have chosen to do so. The president of the company, his wife and their children are also getting chips implanted in their hands.
The chip is about the size of a grain of rice. Implanting the chip only takes about a second and is said to hurt only very briefly. The chips go under the skin between the thumb and forefinger. With a chip in the hand, a person can enter the office building, buy food, sign into computers and more, simply by waving that hand near a scanner. The chips will be also used to identify employees. Employees who want convenience, but do not want to have a microchip implanted under their skin, can wear a wristband (腕带) or a ring with a chip instead. They can perform the same tasks with a wave of their hands as if they had an implanted chip.
Three Square Market is the first company in the United States to offer to implant chips in its employees. Epicenter, a company in Sweden, has been implanting chips in its employees for a while.
Three Square Market says the chip cannot track the employees. The company says scanners can read the chips only when they are within a few inches of them. “The chips protect against identity theft, similar, to credit cards.” The U.S. Food and Drug Administration approved the chips back in 2004, so they should be safe for humans, according to the company.
In the future, people with the chips may be able to do more with them, even outside the office. Todd Westby is Chief Executive Officer of Three Square Market. He says, “Eventually, this technology will become standardized allowing you to use this as your passport, public transit, all purchasing opportunities, etc.”
1. What is the third paragraph mainly about?| A．The substitutes of the chips. |
| B．The advantages of the chips. |
| C．The places to implant the chips. |
| D．The potential risks of implanting the chips. |
| A．the hands | B．the employees | C．the credit cards | D．the scanners |
| A．the chips are very popular among the employees |
| B．the chips have magic powers |
| C．the price of the chips is reasonable |
| D．most people suspect the application of the chips |
| A．Defensive. | B．Disappointing. | C．Optimistic. | D．Casual. |
