| A．The summer this year is terribly hot. | B．Last summer was even hotter. |
| C．Hot weather helps people lose weight. | D．Light was stronger this morning. |
| A．The pollution in the air. |
| B．Smoke coming from the school. |
| C．Measures taken by the school. |
3 . Not all birds sing, but those that do—some several thousand species—do it a lot. All over the world, as soon as light filters over the horizon, songbirds start singing. They sing to defend their territory and to impress potential mates.
“Why birds sing is relatively well-answered,” says Iris Adam, a behavioral neuroscientist at the University of Southern Denmark. The big question for her was this: Why do birds sing so much? “For some reason,” Adam says, birds have “a crazy drive to sing.” This means hours every day for some species, and that takes a lot of energy. Plus, singing can be dangerous.
“As soon as you sing, you reveal yourself,” she says. “Like, where you are, that you even exist, where your territory is —all of that immediately is out in the open for predators, for everybody.”
In a new study published in the journal Nature Communications, Adam and her colleagues offer a new explanation for why birds take that risk. They suggest that songbirds may not have much choice. They may have to sing a lot every day to give their vocal muscles the regular exercise they need to produce top-quality song.
These findings could be related to human voices too. “If you apply the bird results to the humans,” says Adam, “anytime you stop speaking, for whatever reason, you might experience a loss in vocal performance.”
To figure out whether the muscles that produce birdsong require daily exercise, Adam designed a series of experiments on zebra finches —little Australian songbirds with striped heads and a bloom of orange on their cheeks.
Through these experiments. Adam’s conclusion is that “songbirds need to exercise their vocal muscles to produce top-performance song. If they don’t sing, they lose performance, their vocalizations get less attractive to females—and that’s bad.”
This may help explain songbirds’ constant singing. It’s a kind of daily vocal practice to keep their instruments in tip-top shape. It’s a good rule to live by, whether you’re a bird or a human—practice makes perfect, at least when it comes to singing one’s heart out.
1. What does Iris Adam try to figure out?| A．Why all the birds don’t sing. | B．Why songbirds sing so well. |
| C．Why songbirds sing so much. | D．Why birds have vocal muscles. |
| A．Defending territory. | B．Impressing partners. | C．Singing all to death. | D．Threatening lives. |
| A．Regular singing helps to exercise songbirds’ vocal muscles. |
| B．Songbirds have to sing their heart out to win their partners. |
| C．Zebra finches are born to have excellent vocal instruments. |
| D．Good vocal muscles are more attractive to female songbirds. |
| A．A New Study of Songbirds | B．The Way That Songbirds Sing |
| C．Practice Makes a Perfect Song | D．The Reason Why Birds Sing Much |
| A．The Hawaii volcano eruption was destructive. |
| B．What the man said is not currently relevant. |
| C．The man should read newspapers of last year. |
| D．The locals in Hawaii suffered a great deal. |
| A．Birds’ physical characteristics. | B．The migrating patterns of birds. |
| C．The size of bird population. | D．The behavior of migrating birds. |
| A．They become tired of their partners. | B．They can’t reach home at the same time. |
| C．They are likely to find new mates. | D．They have conflicts during the flight. |
| A．They are able to keep pace with their partners. |
| B．They migrate shorter distances than other birds. |
| C．They do not have to migrate for food. |
| D．They have little chance to meet new mates. |
6 . In the rich countries of the West, the electric vehicle revolution is well underway. Climate-conscious consumers drive Teslas or Polestars for reasons of morality and fashion. Poorer countries are also experiencing a wave of electrified trend. In Bangladesh, electric three-wheeler taxis, known as tuk-tuks, are rapidly replacing gas-powered ones on the streets. Such electric vehicles are climate friendly, cost effective, and help reduce air pollution.
Yet a glance under the hood (引擎盖) of these vehicles reveals a poisonous secret: each tuk-tuk runs on five massive lead-acid batteries, containing almost 300 pounds of lead in total. Every year and a half or so, when those batteries need to be replaced and recycled, about 60 pounds of lead leak into the environment. Battery recycling, often at small-scale unregulated factories, is a highly profitable but deadly business.
Lead is dangerous, and any exposure to it is harmful to human health. Lead that has entered the environment hurts people on an extraordinary scale. The numerous ways lead enters air, water, soil, and homes across the developing world — and the enormous damage it does to human health, wealth, and welfare — causes one of the biggest environmental crises in the world yet receives little attention.
The World Bank estimates that lead kills 5. 5 million people per year, which would make it a bigger global killer than AIDS, malaria, diabetes, and road traffic deaths combined. On top of the shocking deaths, the social burden of lead poisoning is extraordinary, as is its contribution to global inequality — our research on the cognitive effects of lead poisoning suggests that it may explain about one-fifth of the educational achievement gap between rich and poor countries.
But unlike many challenges faced by developing countries, lead poisoning is a problem that is fixable with some attention and a relatively modest financial investment. Better monitoring, research, and rules can help protect children all over the world from the dreadful effects of lead poisoning and reduce the massive global costs it brings.
1. How does the author describe the lead problem in paragraph 2?| A．By making a comparison. | B．By analyzing hidden causes. |
| C．By listing convincing numbers. | D．By explaining its working principle. |
| A．Lead enters rich countries in various ways. |
| B．Lead poisoning may make poor societies poorer. |
| C．Exposure to lead doesn’t necessarily harm someone. |
| D．Lead leaking has caused great panic in both countries. |
| A．Fixing these used batteries. | B．Putting certain effort and money. |
| C．Prohibiting the illegal use of lead. | D．Reducing the cost of recycling lead. |
| A．The Impacts of Lead Poisoning on Human Health |
| B．The Outcomes of Using Electric Vehicles |
| C．The Ways to Solve Lead Problem |
| D．The Global Lead Poisoning Crisis |
Are we greening our cities, or just greenwashing them?
Architecture and urban design is chasing a green fever dream. Everywhere you look, there are plans for “sustainable” buildings, futuristic eco-cities and aquaponic farms on the roof, each promising to add a green touch to the modern city.
All of these are surely good ideas at some level. They are trying to repair some of the damage our lifestyle has done to the planet. But, despite the rhetoric of reuniting the city with nature, today’s green urban dream is too often about bringing a technologically controlled version of nature into the city and declaring the problem solved, rather than looking at the deeper causes of our environmental and urban problems.
One of the most striking examples is Apple’s “spaceship” campus now under construction in Silicon Valley. Though it seems to be sustainable and energy efficient—80 percent of its 175-acre site is preserved for landscaping, it is by any measure a huge, expensive and massively resource-intensive project. As a suburban white-collar workplace, it must include vast garages for 13,000 Apple employees. Thus, it will leave no smaller environmental footprint than a traditional office park.
Designing a perfect green building or eco-city isn’t enough to save the world. Although our buildings, like our cars, have been inefficient environmentally, architecture isn’t directly responsible for humanity’s disastrous environmental impacts. An economic system based on the destruction of nature is the real problem. No green building can help us repair the ecological damage we have caused, nor can any number of aquaponic farms bring us back to the real nature.
Instead of adding “nature” to the urban lifestyle, architects may work to design better relationships between our cities and nature, and to promote just relationships between the people in them.
____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________1. What is one suggestion for reducing waste during Christmas gift-giving, according to the passage?
| A．Canceling all the gifts. | B．Applying a “one-gift” rule. |
| C．Giving children less time to play. | D．Encouraging buying second-hand gifts. |
| A．Buying a rare and expensive souvenir. | B．Buying a hand-made craft product. |
| C．Giving something that won’t cost money. | D．Giving an experience of something new. |
| A．The waste caused by Christmas gifts. |
| B．The importance of buying gifts for children. |
| C．The creative ideas of giving gifts to avoid waste. |
| D．The negative effects of receiving too many gifts. |
| A．Its regular driving practices and poor vehicles. |
| B．Its lack of green spaces and air cleaners. |
| C．Its excessive water pollution and rubbish. |
| D．Its high air pollution and crowded roads. |
| A．Establishing a high interest loan scheme. |
| B．Removing outdated black and white taxis. |
| C．Encouraging customers to create new ideas. |
| D．Making advertisements on old vehicles. |
| A．Because customers are more friendly and richer. |
| B．Because all new cabs provide air-conditioning. |
| C．Because all new cabs are equipped with meters. |
| D．Because car manufacturers can earn extra money. |
1. Why do animals evolve to have long body parts?
| A．To detect potential danger in cold places. |
| B．To generate more heat within their bodies. |
| C．To keep their babies warm in breeding seasons. |
| D．To get rid of extra heat with bigger skin surface. |
| A．Wood mice. | B．Bats in warm climates. |
| C．Bird species. | D．Kangaroos in Australia. |
| A．Animals cope with body changes. | B．Joel Allen’s rule is out of date. |
| C．Climate change poses threat to species. | D．Animals adapt to a warmer world. |
