1 . By flying in silence, the owl (猫头鹰) holds a deadly advantage over its prey (猎物), which is thought to have no idea of its hunter’s approach until its final moments.
Researchers have spent more than 80 years trying to solve the mystery of how owls, unique among birds, slice through the air creating just a whisper of audible (听觉的) disturbance. They hope to make use of the findings to reduce the noise generated by aircraft wings, fans and wind turbine blades (涡轮机叶片).
Extensive progress has been made, including developing innovations that have reduced noise from a wind turbine by as much as ten decibels (分贝), the difference between passing car and a passing truck, according to the authors of the study, Justin Jaworski and Nigel Peake.
However, in the study, published in the Annual Review of Fluid Mechanics, they conclude that “the primary barrier to the design of owl-inspired technologies remains the lack of understanding of the essential physics of silent owl flight”. The slight swoosh (嗖) made by an incoming barn owl is below the reach of human hearing until the bird is just under one metre away, laboratory measurements have shown.
In 1934, Robert Rule Graham, a British bird enthusiast and pilot, noted three structural aspects of owl wings that may help to explain their quiet approach: an unusual “comb” structure projecting from the wing’s leading edge, a soft layer of downy feathers that covers most of the wing and a ragged fringe (外围) of feathers that line the trailing wing edge. His theory is widely cited (引用).
Some researchers found that many larger owl species, such as the barn owl, can continuously track their prey in flight by hearing alone, meaning that any aerodynamic noise does not interfere with their tracking ability. When an aeroplane lands, much of the noise comes not from its engines but from the flow of air rushing around it. The ragged, feathered fringes of the owl’s wings may help to reduce the noise.
1. What is the purpose of the researchers’ study on owls?| A．To understand the flying techniques of owls. |
| B．To increase the flying speed of aircraft. |
| C．To help hunters catch their preys with ease. |
| D．To put the secret of owls’ quiet flight to use. |
| A．compare the noise of cars with that of trucks |
| B．illustrate the great achievements of the research |
| C．show the striking difference between trucks and cars |
| D．explain there is still a long way to go in reducing noise |
| A．Lacking the source of inspiration. |
| B．Limited sense of hearing of human beings. |
| C．Failing to understand how owls fly silently. |
| D．Blindness to the structure of owls’ wings. |
| A．Owls don’t move their wings when hunting for their prey. |
| B．The flying barn owl can follow their prey just by hearing. |
| C．Much of the plane’s noise comes from its engines when landing. |
| D．The feathered fringes of the owl’s wings generate the flow of air. |
2 . Visitors won’t find many straight rows in the organic garden at Martin Luther King Middle School in Berkeley, California. Sometimes the beds look like hearts, eyes, question marks or a rainbow. And then there’s the lovely drainage ditch (水沟), called the “Middle River,” which laughing, muddy students carved right down the center of their one-acre land.
As he looks around, Kelsey Siegel, the young teacher in charge of the garden, can’t help but smile. “So many of the youth we work with have grown up in front of TV and video games; they haven’t really had this experience of playing in the mud and water,” he notes. The schoolyard farm “fills in something that’s missing in their lives.”
Before they planted their garden five years ago with the help of highly-praised chef Alice Waters, few of the students at this multicultural Northern California school had even tasted vine-ripened (藤熟的) tomatoes, let alone raised them seedlings. Teachers worried that some children weren’t eating enough fresh fruits and vegetables at home, and the school wasn’t much help either: Like many state campuses, King replaced its hot-meal cafeteria years ago with a more cost-effective outdoor “snack-shack (小吃棚).”
For Waters, the founder of Berkeley’s Chez Panisse restaurant, the thought of children having to rely on such reheated junk — right in her own backyard — was too much to stomach. The small, visionary (有远见卓识的) woman is widely regarded as the Julia Child of organic cuisine in America, the person who’s taught millions the joy of cooking simple dishes with locally grown, chemical-free produce. Waters remembers poking (戳) at mystery food in her school cafeteria as a kid. But today, she says, the spread of vending machines and fast food in America’s schools has become downright evil. “What is it, one in three kids is overweight now? It’s just horrifying,” she sighs, drinking mineral water at a quiet table downstairs in her hugely popular restaurant, about a mile from the King campus “I don’t know what has to happen before we wake up.”
1. What does paragraph 1 highlight?| A．Students’ creativity in farming the schoolyard. |
| B．Students’ knowledge of building the schoolyard. |
| C．The strange look of the organic garden. |
| D．The nice environment of the organic garden. |
| A．unnoticeable | B．predictable | C．modest | D．far-reaching |
| A．Waters preferred fast-food to her school’s mystery food. |
| B．Waters is indifferent to what is happening to children. |
| C．Waters has taught people to grow organic plants. |
| D．Waters is deeply concerned about students’ diet and health. |
| A．Field of dreams | B．Garden of pleasure |
| C．Junk-free restaurant | D．Cost-effective campus |
3 . Perhaps one day, robots could be cleaning up human-caused pollution in the ocean. At least that’s what scientists hope to achieve with the development of Jellyfish-Bot (水母机器人), a robotic device which looks like a jellyfish that could help pick up pollutants underwater.
The robot is about the size of a hand. The artificial muscles, called HASELs, can contract and expand, allowing Jellyfish-Bot to move through the water. Like a real jellyfish, the robot’s movements create currents beneath it. Jellyfish use the currents to collect nutrients, while Jellyfish-Bot uses these motions to trap pollutants. The robots move at a speed of 6.1 centimeters per second, trapping objects along the way, whether it’s a single robot or multiple ones working together. With larger objects, it may require at least two robots to collect and bring the items to the surface for recycling.
“It is also able to collect fragile biological samples such as fish eggs. Meanwhile, there is no negative impact on the surrounding environment. The interaction with aquatic (水生的) species is gentle and nearly noise-free,” explained Tianlu Wang, a postdoctoral researcher.
According to the researchers, the robot is no louder than background noise, so it shouldn’t menace sea life. The insulating polymer (绝缘聚合物) shell around the robot shouldn’t harm humans or fish if it were to be torn apart.
For now, the robots are powered by thin wires, which prohibits their practical use in oceanic settings. But the scientists hope that they can achieve a wireless Jellyfish-Bot in the near future.
“Seventy percent of oceanic litter is estimated to sink to the seabed. Plastics make up more than 60% of this litter, taking hundreds of years to degrade. Therefore, we saw an urgent need to develop a robot to move or control objects such as litter and transport it upwards,” Scientist Hyeong-Joon Joo said. “We hope that underwater robots could one day assist in cleaning up our oceans.”
1. What is paragraph 2 mainly about?| A．The working principle of Jellyfish-Bot. |
| B．The main parts of Jellyfish-Bot. |
| C．The effect of the robot on the ocean. |
| D．The threat of pollutants to the ocean. |
| A．Destroy. | B．Threaten. | C．Transform. | D．Dominate. |
| A．They have been widely used underwater. |
| B．They lack practical use in oceanic settings. |
| C．They will take the place of the wire robots. |
| D．They will be researched and developed for use. |
| A．It’s of great urgency to clean up ocean pollutants |
| B．A new function of robot is just around the corner |
| C．Jellyfish-Bot makes a lot of difference to the ocean |
| D．An underwater robot could help clean up ocean pollutants |
I’m a talker—I have a habit of talking to every person I see—but that afternoon in March 2015, I sat beside my husband Andy on the 45-minute drive home from the Marcus Autism Center without saying a word. My two-and-a-half-year-old son Wesley had just been diagnosed(诊断) with autism spectrum disorder (自闭症谱系障碍).
I’d been given instructions and suggestions and told to sign up for classes, but I knew we could never afford any. Out of everything the specialists had said, the only word I could remember was socialization-key for Wesley to develop social skills. In the car, I tried hard to come up with ways to make his world more social. Then the strangest idea came to mind, so strange that I blurted (脱口而出) it out. “We need a dog!”
Andy looked at me as if I were crazy. “What are you talking about, Rachel? You don’t ever really like dogs.” That was true. I had had bad experiences with dogs growing up. “And how are we going to afford a dog right now?” Yes, another big question. But somehow I couldn’t shake the idea.
A couple of weeks later, I was outside playing with Wesley, when a new neighbor walked over with a black curly-coated dog. When we were chatting, her medium-sized dog ran and jumped playfully between the boys. He was so gentle; he didn’t jump on people the way I’d seen a lot of dogs do. I watched, amazed. It was as if he knew exactly how careful to be with each of them.
“What breed (品种) is he?” I asked. “He’s an Aussiedoodle (贵宾澳牧),” She said proudly. Then she continued, “He was bred (培育) by a woman called Mary, who has three autistic (自闭症的) sons. She found that Aussiedoodles work perfectly as service dogs. I can give you her phone number if you want one.”
注意：
1.续写词数应为150左右;
2.请按如下格式在答题卡的相应位置作答。
“Was this for real? We need an Aussiedoodle!” I said.
____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________
Then Andy and I drove to Mary’s home, and picked a dog called Berry.
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5 . Gardening’s many “rules” have been repeated so often that they can seem like unquestionable truths. But many have little basis in fact, so following them may be unnecessary at best and could give you poorer results at worst.
A classic example is the long-held idea that watering plants around noon on a sunny day should be avoided, since it might harm their leaves. The explanation is that tiny water droplets can act like lenses (透镜), focusing the sun’s rays onto leaves, resulting in scorched (灼伤的) leaves and reduced plant health.
Four researchers set out to learn more, running experiments on living plants and carrying out computer modelling. They found that spreading small glass spheres (球体) over the surface of smooth-leaved plants could indeed have this effect, causing damage right across the leaf surface. But when this was repeated with actual water droplets, such damage didn’t occur.
This is because water behaves rather differently to glass. The shape of a water droplet on a leaf is more elliptical (椭圆的) than spherical. The computer modelling showed that the extreme damage through a lens of this shape would occur when the sun was at a low angle in the sky, that is, in the morning or in the afternoon. However, the sun’s strength at these times is too low to cause any harm. Even if the light of the midday sun did somehow come at the strongest angle, the heat at this time of day would always cause the water droplets to evaporate (蒸发) before they had an effect.
So, if your plants need a good watering, give them some water. Not watering thirsty plants on a sunny day for fear of leaf scorch will almost certainly lead to more damage from drought stress than could be caused by the magnifying glass (放大镜) effect. While it remains generally true that the ideal time to water a plant is in the morning or evening — to lessen the amount of water that evaporates before reaching the plant’s roots — the evidence doesn’t support the idea that watering at midday will cause burning.
1. What is the long-held idea talked about in the passage!| A．Watering plants counts a lot. |
| B．Plant leaves might act like lenses. |
| C．Watering at midday may harm plant health. |
| D．Sun’s rays might be focused onto water droplets. |
| A．The same degree of damage occurred. |
| B．Damage was caused right across the leaf surface. |
| C．Unlike the glass spheres, the water droplets didn’t damage leaves. |
| D．The smooth-leaved plants were extremely affected by water droplets. |
| A．The explanation for the finding. |
| B．The process of the experiments. |
| C．The time of evaporating. |
| D．The harm caused by the sunshine. |
| A．The long-held idea is well worth advocating. |
| B．Plants’ roots get no water if watering occurs at noon. |
| C．Watering in the morning can prevent water evaporation. |
| D．Watering thirsty plants on a sunny noon makes sense. |
6 . Scientists say a huge percentage of bird species are in danger because their habitats, or homelands, are disappearing.
Traditional migration paths take birds through countries that are not protecting the places for birds to stop, rest and feed. The scientists studied the migration or flight paths of almost 1,500 species. They decided that 91 percent of them passed through dangerous areas.
The major danger for migratory birds is development. Buildings and pavements have covered the places where birds stop and feed as they move from one part of the world to another. One of the scientists who worked on the study says “Many of these important places have been lost to land reclamation because of urban, industrial and agricultural land expansion”.
The problem, according to scientists, is that many of these small birds die along their migration paths because they don’t have a safe place to feed and rest. There is no place to restore their energy for the next part of their journey. Countries in North Africa, Central Asia and those along the coasts of East Asia are having the most difficult time in protecting land. The scientists say these countries do not have enough areas that are safe for birds. One species that doesn’t exist now is the Eskimo curlew. “Our world gets poorer every time we lose a species,” one of the scientists says.
The researchers say countries need to work together and come up with safe stopping areas for birds that pass through their boundaries. For example, one country might have preserved safe zones for migrating birds. But a neighbor country might not. A bird might die.
One scientist who is not connected with the report tells Los Angeles Times that while some habitats are changing, more work can be done to make urban areas safe for birds.
He says small changes, like planting more native plants or keeping cats out of the areas birds would be likely to use, could make a big difference.
1. What mainly caused the disappearing of birds’ habitats?| A．The decrease of awareness to protect birds. | B．Natural disasters. |
| C．Overuse of land by human beings. | D．The rising sea level. |
| A．Tiredness and hunger. | B．Beast attack on the ground. |
| C．Hunting of humans. | D．The long journey. |
| A．By keeping fewer cats or dogs. |
| B．By restoring their destroyed habitats. |
| C．By helping change the birds’ migration paths. |
| D．By preserving the ecological environments on their migration paths. |
| A．To call on people to protect the birds’ habitats. |
| B．To analyze the reasons for disappearing of birds’ habitats. |
| C．To offer some solutions to the problem of birds’ habitats. |
| D．To tell us a huge percentage of bird species are in danger. |
7 . Didga, the skateboarding cat
I have three cats. Didga is the most eye-catching. In terms of skills, there is no cat in the world that can be
I’ve been an animal-trainer for 40 years. Everyone said cats can’t be trained. Thus, I wanted to
I went to an animal shelter (动物收容所). As I was walking through, a kitten
Before long, Didga
However, training with cats isn’t
In 2017, Didga accomplished a tough task to perform 24 different tricks in
Didga has
| A．used | B．equal | C．blind | D．devoted |
| A．prefer | B．press | C．prove | D．prevent |
| A．fell | B．followed | C．left | D．travelled |
| A．hesitation | B．money | C．recognition | D．response |
| A．rose | B．added | C．tended | D．adapted |
| A．hopefully | B．passively | C．willingly | D．energetically |
| A．care | B．company | C．protection | D．help |
| A．horrible | B．hard | C．slow | D．smooth |
| A．matters | B．pays | C．spends | D．takes |
| A．individually | B．immediately | C．luckily | D．eventually |
| A．Skiing | B．Swimming | C．Skateboarding | D．Surfing |
| A．appealed | B．connected | C．attached | D．compared |
| A．over | B．under | C．beyond | D．below |
| A．shown | B．had | C．caused | D．made |
| A．bring up | B．bring about | C．bring out | D．bring back |
8 . A bear that wandered what is now China about six million years ago is the oldest bamboo-eating panda ancestor yet found-and it had the same short and fat false thumbs that stick from the wrists of today’s pandas alongside their five fingers. Fossils(化石) of the new species suggest such “thumbs,” which helped the animals eat bamboo, maintained their peculiar shape to facilitate the beast’s four-legged movement.
The fossils, found in the province of Yunnan and described in Scientific Reports, also push back the date that pandas’ ancestors likely changed from eating meat to chewing bamboo-from two million to six million years ago. “Giving up on a meat-eating diet means trading the unstable life of a meat-eater for quiet consumption of the plentiful bamboo,” says paleontologist and study lead author Xiaoming Wang of the Natural History Museum of Los Angeles, adding that it was “not a bad deal.”
Although the fossils dug from the province’s Zhaotong Basin included only teeth and some limb(肢) bones from the bear, these were typical enough for Wang and his colleagues to identify the fossils as belonging to an early member of the panda lineage called Ailurarctos. A wrist bone in the collection, with its proto-thumb, stands out among the remains. “Its structure is really close to that of the living panda,” says Juan Abella Pérez of Miquel Crusafont Catalan Institute of Paleontology in Barcelona, who was not involved in the new study.
Why didn’t this short and fat thumb evolve into a longer, larger false thumb to better grasp a meal? The researchers propose that walking on all fours was the key reason. If the panda’s thumb were larger, Wang and his colleagues suggest, the appendage(附属物) could have affected its walking or faced a high risk of breaking. In a sense, this makes the evolution of the panda’s thumb all the more impressive. The structure was limited by the need to move as well as to eat.
1. What inspired the scientists’ research?| A．Pandas. | B．Bears. |
| C．Fossils. | D．Bamboos. |
| A．Bamboo tasted better. |
| B．They found bamboo sufficient. |
| C．They knew it was a good deal. |
| D．They were tired of eating meat. |
| A．It’s convincing. |
| B．It matters little. |
| C．It’s misleading. |
| D．It remains to be tested. |
| A．Where pandas’ ancestors lived. |
| B．What contributed to pandas’ movement. |
| C．How pandas’ ancestors began to eat bamboo. |
| D．Why pandas’ ancestors possessed such thumbs. |
9 . Birds’ bodies are becoming smaller in size in response to climate change, even in places like the Amazon rainforest that are relatively untouched by human hands, according to a new study published in the journal Science Advances.
Researchers found that nearly all of the birds’ bodies have become lighter since the 1980s, losing on average about 2% of their body weight every decade. For an average bird species that weighed about 30 grams in the 1980s, the population now averages about 27.6 grams. The study also revealed that wingspan was getting bigger in the Amazon bird species studied.
These birds don’t vary that much in size. When everyone in the population is a couple of grams smaller, it’s significant. This is undoubtedly happening all over and probably not just with birds.
A lower body weight and increasing wing length means that birds use energy more efficiently, the researchers noted. For example, compared with a fighter jet with short wings that needs lots of fuel to fly, a glider plane with a thin body and long wings flies up into the air with much less energy.
The study concluded that a warmer climate was the driving force of these changes. The climate in Brazilian Amazonia, where the birds lived, had gotten hotter and wetter over the study period. Since 1966, rainfall increased by 13% in the wet season and fell by 15% in the dry, with temperatures increasing by 1 degree Celsius in the wet season and 1.65 degrees Celsius in the dry season. The change in climate might have made food or other resources insufficient.
Together, body proportions moved in the direction of more efficient flight and lower metabolic heat production and are consistent with a plastic or genetic adaptation to resource or thermal stress under climate change.
Animals are dealing with climate change in different ways.
1. What is the direct cause of birds’ changes?| A．A warmer climate. | B．A scientific advance. | C．A lack of sufficient food. | D．A lack of drinking water |
| A．To show planes fly with much less fuel. | B．To prove birds need much energy to fly. |
| C．To demonstrate birds’ efficient energy use. | D．To illustrate planes need lots of fuel to fly. |
| A．Animals’ other body part changes. | B．People’s attempts to protect animals. |
| C．Birds’ adaptation to climate change. | D．Animals’ ways to tackle climate change |
| A．Birds Nowadays Also Have to Adapt to Climate Change |
| B．The Climate Crisis Is Influencing Birds’ Body Shapes |
| C．It’s Our Duty to Take Measures to Protect Birds on the Planet |
| D．It’s Time to Raise Human Beings’ Awareness of Climate Crisis |
10 . I've spent all my adult life working with trees. Recently, our fundraising team was looking for novel suggestions to raise money to help
They knew I'd been a tree hugger since a very early age. Still,I wasn’t
My tree hugging practice is simple: making maximum contact.This means wrapping my arms as
I'm delighted that we
Tree hugging is a wonderful way of reconnecting with
| A．plant | B．save | C．grow | D．water |
| A．requested | B．ordered | C．insisted | D．suggested |
| A．sure | B．surprised | C．curious | D．confused |
| A．donate | B．make | C．burn | D．raise |
| A．visit | B．try | C．thought | D．decision |
| A．carefully | B．straight | C．far | D．tightly |
| A．Surprisingly | B．Fortunately | C．Definitely | D．Strictly |
| A．laughed | B．walked | C．accepted | D．advocate |
| A．figid | B．new | C．brilliant | D．unusual |
| A．possible | B．hopeless | C．good | D．complex |
| A．managed | B．tried | C．wanted | D．started |
| A．creation | B．target | C．value | D．profit |
| A．man | B．life | C．society | D．nature |
| A．gentle | B．fast | C．relaxed | D．lively |
| A．freedom | B．bravery | C．patience | D．kindness |
