Do you drink water that's been left sitting out overnight or even for another day? Have you noticed it tastes different?
Tap water that has been left to sit out slowly begins to acquire(获得) an off taste. Many people think that this is because of microorganisms. But that's not what makes old water taste not fresh. For that we can thank carbon dioxide. After about 12 hours, tap water starts to go flat as carbon dioxide in the air starts to mix with the water in the glass, lowering its pH and giving it an off taste. But it's most likely safe to drink.
However, back to those microorganisms. If you use a dirty glass day after day, there is more of a chance of bacteria making themselves known; a risk that increases if you share the glass with another mouth as well. But assuming(假设) you use a fresh glass every few days, you probably won't have a problem unless the glass has been touched by dirty fingers, and especially if those dirty fingers went unwashed after using the bathroom.
As for plastic water bottles that have been left out in the sun or in the car, step away from the bottle, warns Dr. Kellogg Schwab, director of the Johns Hopkins University Water Institute. "A chemical called bisphenol-A, or BPA, along with other things used to make plastic can leach(过滤) into your water if the bottle heats up or sits in the sun," he explains. BPA, as you probably know, has been linked to everything from heart disease to cancer. Schwab also adds that plastic used for commercial bottled water isn't meant to be washed or refilled, so use only one time and recycle. Or don't buy them at all; use refillable water bottles instead.
1. Tap water begin to acquire an off taste because of______ .| A．BPA | B．carbon dioxide |
| C．the glass | D．the microorganism |
| A．is still safe to drink | B．tastes better |
| C．contains few microorganisms | D．is most likely undrinkable |
| A．Throw them away. |
| B．Clean them and use them again. |
| C．Use them after they cool down. |
| D．Refill them with fresh water. |
| A．It is safe for people to use. |
| B．It is a kind of new material. |
| C．It can cause great harm to people. |
| D．It is the main material to make plastic. |
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【推荐1】Rising Seas Will Erase More Cities by 2050, New Research Shows
Rising seas could affect three times more people by 2050 than previously thought, according to new research, threatening to all but erase some of the world's great coastal cities.
The authors of a paper published on Tuesday developed a more accurate way of calculating land elevation based on satellite readings, and found that the previous numbers were far too optimistic. The new research shows that some 150 million people are now living on the land that will be below the high-tide line by mid-century. In Thailand, more than 10 percent of citizens now live on the land that is likely to be covered with water by 2050, compared with just 1 percent according to the earlier technique. The political and commercial capital, Bangkok, is particularly dangerous.
In other places, the migration caused by rising seas could cause or worsen regional conflicts. Basra, the second largest city in Iraq, could be mostly underwater by 2050. If that happens, the effects could be felt well beyond Iraq's borders, according to John Castellaw, a retired Marine Corps general.
“Further loss of land owing to rising waters there threatens to drive further social and political instability in the region, which could lead to armed conflicts again and increase the likelihood of terrorism,” said Castellaw, who is now on the advisory board of the Center for Climate and Security, a research and advocacy group in Washington. “So, this is far more than an environmental problem,” he said. “It's a humanitarian, security and possibly military problem too.”
1. How many people will be threatened by 2050 according to the research?| A．About 15 million. | B．About 50 million. |
| C．About 150 million. | D．About 450 million. |
| A．The migration caused rising seas. |
| B．Basra could be entirely underwater by 2050. |
| C．Rising seas could erase all the world's great coastal cities. |
| D．Further loss of land owing to rising waters could cause armed conflicts. |
| A．To advise people to move house. | B．To tell new research. |
| C．To warn the danger of conflicts. | D．To appeal for environmental protection. |
| A．A science magazine. | B．A geography textbook. |
| C．Science fiction. | D．A medical journal. |
【推荐2】As people in southern Florida prepared for Hurricane Irma, many included four-legged family members in their plans. Even with the best plans, though, pets can get lost in a natural disaster. Animal rescue organizations like ASPCA see an increase in lost animals after storms.
Some pets get frightened and run away. Others hide in places where their owners can’t find or reach them. Then, in the confusion of an evacuation, they get left behind. “We strongly suggest families should not evacuate without their pets. If it’s too dangerous for you, it’s too dangerous for your pet,” says Tim Rickey, vice president of Field Investigations and Response at the ASPCA.
An owner’s first and best defense against losing a pet is to have the animal microchipped (植入芯片) and registered. The cost of a microchip is around $50. Any vet (兽医)can put the microchip under the pet’s skin. Owners can then register the pet with the company that makes the microchip. There’s also a “universal” database (数据库)that will search all of the different chip companies. The human just has to provide contact information for the pet in the chip’s database, and then keep that information current. “All too often, people change phone numbers or they move, but they don’t remember to update their pet’s information,” Rickey says.
Other ways Rickey recommends depend on an owner’s knowledge of their pet. Does Fido or Fluffy tend to make a run for it when they get frightened? Then it might be time to buy an extra-strong leash and collar, and keep an extra-close watch. If your pet prefers hiding, create a safe shelter for them that is also easy to be found. That way, you’ll know where to look first in case everyone needs to make a quick getaway.
1. What does the writer intend to tell us in paragraph 1?| A．Hurricane often hits southern Florida. |
| B．Pets are often left behind in natural disasters. |
| C．Pets are important members of many American families. |
| D．Rescue organizations are set up to help animals in danger. |
| A．To create a secret hiding place for pets. |
| B．To have a good knowledge of natural disasters. |
| C．To keep the pet owner’s contact information unchanged. |
| D．To depend on the application of microchips and databases. |
| A．A magazine. |
| B．A brochure. |
| C．A biology book. |
| D．A scientific report. |
【推荐3】Animal Families, Animal Friends (NorthWord Books for Young Readers) is all about how animals work and play together, and how they help one another and keep each other safe.
I got the idea for this book from an article I read in a science magazine. It talked about how scientists, who used to focus on how animals compete in nature, are now studying how they coexist peacefully and even help each other.
I decided to write a book for children on the subject. I had lots of fun doing research for this book, I went to the library first and read about all sorts of animals. Then I made my choices based on my reading and my own experience. I love the sound of loons calling at night on a Maine lake. I watched beavers build a home on a stream in the Maine woods. I watched dolphins swim and dive alongside my sailboat in California. I visited Mission Wolf, a wonderful wolf refuge in Colorado. I saw prairie dogs in the Badlands of South Dakota.
I haven’t seen some of the animals in the wild—elephants, chimpanzees, caribou, emperor penguins. But I read books and watched videos online to learn how they live together. Who can watch the film March of the Penguins and not fall in love with them?
I used the Internet to listen to the sounds these animals make. And I made a collection of stuffed animals and puppets for my school presentation of Animal Families, Animal Friends.
Now I’m having a wonderful time visiting schools, libraries, and even a zoo to talk about the animals in my book. A highlight of these visits was a few days spent in Ocean Springs, Mississippi, speaking to children whose town was hit by Hurricane Katrina in 2005. These children, their families, and their communities have given us all a fine example of how to live together and help each other.
1. What is the author’s purpose in writing Animal Families, Animal Friends?| A．To help adults know animals better. |
| B．To raise public awareness of wildlife protection. |
| C．To report some latest findings about the animal world. |
| D．To inform children how animals coexist with each other. |
| A．By visiting zoos. | B．By analyzing previous data. |
| C．By taking advantage of the Internet. | D．By consulting experts. |
| A．It is an environment-friendly place. | B．People there live together harmoniously. |
| C．People there get on well with animals. | D．It was hit by Hurricane Katrina in 2005. |
| A．Confused. | B．Anxious. | C．Content. | D．Tired. |
【推荐1】People who grow up left-handed have a different, more flexible brain structure than those born to take life by the right hand, say researchers at the University of California, Los Angeles.
The reason is that right-handers have genes that force their brains into a slightly more one-sided structure, according to the research. Left-handers appear to be missing those genes.
"There really is a difference in brains that results in a more symmetric (对称的) brain in left-handers, where the two sides are more equal," said Daniel Geschwind, who led the research team.
In the effort to understand how the brain shapes the mind, researchers have been trying to document the way genes and environment affect intelligence and mental abilities. They found that right-and left-handedness is determined by genetics. If a person has the gene for right-handedness, that person will be right-handed. People who do not have that gene, however, can be either left- or right-handed. There is no specific gene for left-handedness.
Right-handers typically have a larger left brain, where their language abilities are concentrated. Conversely, left-handers have more balanced brains. The language abilities of left-handers more often, are concentrated on the right side.
The UCLA researchers conducted brain scans on 72 pairs of male identical (同卵双生的) twins between 75 and 85 years old. They noticed that if identical twins carry the gene for hand preference, both must be right-handed. If they lack the gene, one twin can develop right-handed while the other can develop left- handed.
The researchers found that the brains of identical right-handed twins were very similar in size and structure. But when a left-hander was part of the twin set, the brains were different. The conclusion, researchers said, is that the absence of the gene for hand preference allows the brain to develop differently as the individual grows up.
1. What is the finding of the researchers of UCLA?| A．Left-handers have more balanced brains. | B．Right-handers have more flexible brains. |
| C．Left-handers' brains are more one- sided. | D．Right-handers' brains are more symmetric. |
| A．Environment. | B．Intelligence. |
| C．Habit. | D．Gene. |
| A．They always have similar brain structure. |
| B．They never carry the gene for hand preference. |
| C．They have different genes for hand preference. |
| D．They can have different hand preference. |
| A．People's genetic makeup. | B．People's hand preference. |
| C．People's brain sizes. | D．People's communicative skills. |
【推荐2】Humans are not the only ones that like gold. Australian scientists have discovered a new fungus(真菌)that decorates its long,thread-like tendrils(卷须)with gold collected from the soil. The experts desperately hope the “gold digger” will provide information on the locations of gold deposits(沉淀物)and make searching for the precious meal easier, and more environmentally friendly.
The gold-loving fungus was discovered accidentally by a team of researchers led by Dr. Tsing Bohu, a scientist at Australia national science agency, CSIRO, when they were examining the microbes(微生物) in the soil at Boddington,a tiny town home to Australia’s largest gold mine.
A closer analysis suggested that the fungus uses chemical interactions with underground minerals to accumulate gold from its surroundings. Though fungi often interact with other things in nature, the reaction with gold was unexpected. “Fungi are well-known for playing an important role in the recycling of organic material, such as leaves and bark, as well as for the cycling of other metals,” Dr. Bohu explained. “But gold is so chemically inactive that this interaction is both unusual and surprising.”
The fungi are not wearing the gold for beauty. “There is a biological benefit from this reaction.” Dr. Bohu said, “Gold-loving fungi can grow faster and bigger relative to other fungi that don’t work with gold.”
The researchers still need to conduct further analysis to understand the relationship between the fungi and the precious metal. More importantly, they need to determine if its presence is a sure sign of the existence of large deposits of the metal underground. The scientists also believe the fungi could be used to detect the presence of gold in waste products and man-made electronics.
However, those hoping to get free gold from the fungi are in for a disappointment,for the delicate fungus is hard to see. Also, its gold can only be seen under a microscope.
1. What are the experns starved of?| A．Investigating the sites. | B．Excavating the gold mines. |
| C．Getting further informed. | D．Unearthing gold deposits. |
| A．Fungi’s interaction with gold is unexpected but beneficial. |
| B．Gold’s classification is biologically identified by fungi. |
| C．Fungi’s formation with gold is fairly natural and frequent. |
| D．Gold is chemically accuniulated by fungi’s evolution. |
| A．It excites the gold diggers’ motivation. | B．It has a long way to go before confirmation. |
| C．It lays the foundation of geologieal studies. | D．It ensures the search of gold sites. |
| A．Beauty-loving Fungi Wrapped by Gold | B．Gold-loving Fungi Discovered in Australia |
| C．Boddington, Austria’s Largest Gold Mine | D．New Discovery of Gold with Fungi |
【推荐3】A complete chicken egg estimated to be around 1,700 years old is believed to be the only of its type in the world, after scientists found it still had liquid inside.
It was discovered during a dig in Aylesbury in Buckinghamshire between 2007 and 2016, with researchers saying at the time that it was a “genuinely unique discovery”. During the course of the dig, archaeologists broke three other eggs which released a “terrible smell”, but a fourth egg remained undamaged. It is the only complete egg ever found dating back to the Roman times.
Now, a micro scan has found that the egg still contains the yolk (蛋黄) and egg white, and it is believed to be the only complete egg from that period. The recent work has been carried out by conservator Dana Goodburn-Brown, who took the egg for further analysis at the University of Kent.
Edward Biddulph, senior project manager at Oxford Archaeology, who oversaw the dig, said, “It produced an amazing image that indicated that the egg, apart from being complete — which is incredible enough — also held its liquid inside. We were absolutely blown away when we saw the contents in there, as we might have expected them to have leaked out.”
It has also been taken to London’s Natural History Museum, where Douglas Russell, the senior director of the museum, was consulted about how to conserve the egg. Mr Biddulph said, “As we found out when we visited the Natural History Museum, it appears to be the oldest known example in the world.”
The egg is now being housed at Discover Bucks Museum in Aylesbury while work continues to discover how to extract (提取) the inside without breaking the delicate shell.
“There is huge potential for further research and this is the next stage in the life of this remarkable egg,” Mr Biddulph said.
1. Why was Edward Biddulph shocked at the egg?| A．It was badly preserved. | B．It could be blown away. |
| C．It kept liquid contents inside. | D．It was still good enough to eat. |
| A．The egg will be broken for further study. |
| B．The egg will be on display in the museum. |
| C．More studies will be carried out about the egg. |
| D．More efforts will be put into studying the egg shell. |
| A．The Secret of an Ancient Egg Has Been Revealed |
| B．An Ancient Egg Reveals the History of Buckinghamshire |
| C．An Egg Is Said to Be the Oldest Complete One in the World |
| D．An Amazing Egg Is Still Full of Liquid 1,700 Years Later |
| A．A news report. | B．A biology essay. |
| C．A technical invention. | D．A geographical discovery. |
【推荐1】As adolescents, having a great impact on the world may seem like an impossible task. Changing the world does not only mean finding a cure for cancer, or finding the origin of human beings, but also recycling some things as well.
Recycle.
According to a report, 63 million newspapers go out to customers every day and of those 44 million are thrown away. Recycling the Sunday newspapers alone we could save half a million trees a week.
The age of technology constantly creates new phones, iPads, or new computers. Many people will stand in line for hours to get their hands on the new technology, but about 75% of the old devices sit in the back of a drawer collecting dust.
Go vegetarian one day a week.
Ditch (丢弃) bottled water.
Most people drink bottled water because of the common conception that bottled water is healthier than regular tap water.
| A．Let's take action right now. |
| B．Having more vegetables is beneficial to our health. |
| C．The following are some astonishing facts about that. |
| D．Actually, 25% of bottled water comes from regular tap water. |
| E．It contributes to 1.5 million tons of plastic ending up in landfills. |
| F．By taking them to the local stores that collect them they go to people in need. |
| G．What follows are three simple ways adolescents can go green and change the world. |
【推荐2】Edward Davis was a professor who worked on ocean research. However, bored with writing death records of ocean species, he quit his job in 2007. Rather than spend any more of his life recording the dying, Edward decided to try to protect the living creatures in the few remaining areas of the ocean.
These areas are the last wild places of the sea still undamaged by overfishing, pollution and climate change. “It is necessary for us to go to places that still look like the ocean as it was 500 years ago,” Edward says. “These places are the examples of sustainable (可持续的) development. Maybe we can’t bring all of the ocean back to this state, but these places show us what the potential is.” Beneath the surface of a stormy sea off Palau in the western Pacific lie various lively corals. The tiny island nation has protected 80 percent of its waters as a no-fishing area — the largest percentage of protected ocean area in the world. The remaining 20 percent can be fished only by Palauans.
To protect these places, Edward and his team started a project on ocean protection in 2008. Over the past years, the project has helped create 22 ocean reserves. These make up two-thirds of the world’s fully protected ocean areas. Now Edward and his team have set an even bigger goal — to protect more than a third of the world’s oceans for the purpose of keeping biological diversity.
For Edward, one of the most satisfying aspects of his job is working with local communities in the places he and his team are seeking to protect. The team worked closely with about 50 local people on the island. “We showed them an underwater world they had never seen,” Edward recalls. “Huge schools of fish will surely swim in some of the clearest waters ever measured in the Pacific.”
1. Why did Edward quit his previous job?| A．To record the dying. | B．To increase land species. |
| C．To protect the sea creatures. | D．To write a book on sea protection. |
| A．20 percent of it is covered by the sea. |
| B．It is an area open to fishermen worldwide. |
| C．It is an example of sustainable development. |
| D．The surface of it is destroyed by water pollution. |
| A．Edward’s team. |
| B．Edward’s project. |
| C．The ways of keeping biodiversity. |
| D．The ways of creating ocean reserves. |
| A．Positive. | B．Stressed. | C．Curious. | D．Confused. |
【推荐3】Because of the development of agriculture, the area of land affected by sand has gradually increased. During the 1950s and 1960s the land affected by sand expanded on average into 1,600 square kilometers per year. By the 1990s, the area had reached 2,500 square kilometers per year. This kind of situation is particularly serious in many regions upwind(逆风的) from Beijing. Fengning City in Hebei Province and Duolun City in Inner Mongolia lie to the north of Beijing, and in the last 50 years the population of these two cities has grown by 2 to 3 times. In order to obtain more resources, the inhabitants have been busy with heavy farming, tree-cutting and keeping animals. The result is that the soil which has sustained damage, and the sand layer below the earth is now exposed on the ground and the ground is rapidly being controlled by the spread of sand.
China has already noticed this problem, and has take measures to save the land. Nowadays, some land used for farming has returned to forestland and grassland. The Chinese government announced that it would invest more than RMB 600,000,000 to control Beijing’s sandstorms in the coming years. Only by decreasing the damage caused by man and restoring the natural environment will it be possible to well control the sources of the sand and dust. We hope in the not-distant future, we will solve the problem successfully and effectively.
1. Compared with 50s and 60s, the land affected by sand increased by________square kilometers by the 1990s.| A．1,600 | B．2,500 | C．900 | D．1,100 |
| A．People use the resources too much. |
| B．People keep animals which need more grain. |
| C．People prepare too much land to grow crops. |
| D．People cut a lot of forests and raise animals. |
| A．controlling the growth of the population |
| B．making better use of natural resources |
| C．killing fewer animals and cutting fewer trees |
| D．returning some land to forestland and grassland |
| A．man | B．animal | C．nature | D．desert |
