Placed among the busy streets of Washington, D. C. is a large public garden that many Americans have never heard of. The U. S. National Arboretum (植物园) includes
Government scientists are in charge of the 180-hectare area. Their main goal is
The arboretum is home to one of the
While the scientists do their work, the public
2 . The Grand Canal, a large waterway that first connected north and south China over 1400 years ago, is shorter than it once was, but it is still the longest man-made river in the world.
The original Canal system began around the year 605. China’s emperor realized that he needed a better way to feed his army. Specifically, he needed a way to move food quickly from China’s southern rice-growing region to the country’s north. Thus, he spent 6 years on construction of the first section of the Grand Canal, connecting existing canals, lakes and rivers. However, by 1127, parts had begun to worsen. In 1279, Kublai Khan began to repair and create a more direct north-south route to and from Beijing.
The Grand Canal was also an important cultural channel. Soldiers, merchants and artists transported ideas, regional foods and cultural practices from one part of China to another. It is said that Peking duck and the Pecking opera were both brought north via the canal. Even today, the country’s watery highway plays an important economic role in China. In addition, local governments, eager to increase tourism and real estate (房地产) development, are beautifying areas along the Canal.
This development comes at a price, though. In Yangzhou, the city government has torn down almost all of the older Canal-side buildings. Farther south in the cities of Zhenjiang, Wuxi and Hangzhou, the situation is similar. “Traditionally, we talk about eighteen main cities on the Grand Canal, and each had something unique and special about it.” explains Zhou Xihua, the director of the Grand Canal museum. “But now many of these cities are all the same: a thousand people with one face.”
In 2005 a group of citizens proposed that the historic Grand Canal be made a UNESCO world heritage site. The status would protect both the waterway and architecture around it. “Every generation wants the next generation to understand it, to look at its monuments.” said Zhu Bingren, an artist who cowrote this proposal. UNESCO status was officially granted in 2014. The hope now is that the grand Canal, one of the world’s great engineering accomplishments, will continue to link north and south China for centuries to come.
1. Why was the Grand Canal originally built?| A．To allow his army to move more quickly. |
| B．To transport food from the south to the north. |
| C．To enable people to visit remote parts of China. |
| D．To promote the cultural and traditional diversity. |
| A．It is the longest man-made river in the world. |
| B．It orginally complete construction in the year 611. |
| C．Its original north-south route is to and from Beijing. |
| D．It allowed Peking duck and the Peking opera to spread. |
| A．Developing the canal involves spending a lot of money. |
| B．Even after spending money, people dislike the development. |
| C．Developing it is more expensive than one can imagine. |
| D．There are some negative consequences to this development. |
| A．The history of the Grand Canal. | B．The introduction of the Grand Canal. |
| C．The construction of the Grand Canal. | D．The proection of the Grand Canal. |
3 . How Weather Affects Our Mood
The weather supplies many metaphors (隐喻) for our changeable minds. Moods can brighten and darken, futures can be under a cloud, and relationships can be stormy.
Of the many aspects of weather, sunshine is the most closely tied to mood. Although the link is weaker than many people imagine, sunlight has repeatedly been found to increase positive moods and reduce tiredness.
Indeed, the effects of weather on mood depend on our behavior and on how we think.
| A．Similarly, grey weather may encourage serious and calm thinking |
| B．Aspects of weather beyond heat and sunshine have also been shown to affect mood |
| C．Weather provides a vivid language for describing our emotional atmosphere |
| D．Temperature can also affect our mind and behavior |
| E．But the effects of weather on mood are not entirely biological |
| F．Anything that changes our moods can affect our behavior |
| G．Basically, weather will only influence us if we are outdoors experiencing it |
4 . Have you heard of shark fin (鲨鱼鳍) soup? This famous and expensive dish is especially popular in southern China. But do you realize that you are killing a whole shark each time you enjoy a bowl of shark fin soup?
When people catch sharks, they cut off their fins and throw them back into the sea where they die slowly and painfully. In fact, around 70 million sharks are caught and traded (交易) in this industry every year. The numbers of some kinds of sharks have declined by over 90 percent in the last 20 to 30 years.
Environmental protection groups around the world, such as WildAid and the WWF, are teaching the public about “finning”. They have even asked governments to develop laws to stop the sale of shark fins. So far, no scientific studies have shown shark fins are good for health, so why eat them? Help save the sharks!
1. Where is shark fin soup especially popular?| A．In eastern China. | B．In southern China. | C．In western China. | D．In northern China. |
| A．Fallen. | B．Added. | C．Doubled. | D．Increased. |
| A．They are afraid of sharks. |
| B．They catch sharks for fun. |
| C．They consider sharks lovely. |
| D．They cut off shark fins for money. |
| A．WTO. | B．UNESCO. | C．WildAid. | D．WHO. |
| A．Respect Nature | B．Value the Planet | C．Save the Sharks | D．Keep Balance |
5 . Long ago, Mexican wolves were common all through the Southwestern US and Northern Mexico. But as more human activities appeared in the areas, the wolves were hunted until they almost died out. The Mexican wolf is the rarest kind of gray wolf in North America. In the1970s, the US government began a program of raising Mexican wolves and releasing (放出) them back into nature. The program hoped to make the wolves spread back across the area they had once lived in for they are an important part of the balance of nature in the area.
The result of the latest count of Mexican wolves was reported by the US Fish and Wildlife Service (USFWS). A total of 42 wolf packs were found in the wild, and half of them had baby wolves last spring. Around 90 baby wolves were born in all, and 58% of them survived. The count reported a total of 163 wolves, which is nearly 25% more than last year. Over the last 10 years, the number of wolves has been increasing by about 15% a year.
One change wildlife managers have made recently is placing little wolves into groups of wild wolves. The wolves that are returned to nature when they are young seem to be far more adaptable than wolves that go into the wild for the first time as adults. Besides, new wolves from outside the packs also improve the overall long-term health of the wolves as a group.
However, not everyone is excited about the news. For farmers, who must protect their cattle from wolves, the increase is likely to mean more lost animals on their farms. Last year, 184 farm animals were killed in all. That’s the largest number since 1998.
Now, the USFWS and others are studying the increase in cattle killings, and trying to figure out solutions to protecting both Mexican wolves and farm animals. Bryan Bird, speaking for a group called Defenders of Wildlife, says, “Ensuring that wolves and people can get along is a necessary part of long-term success.”
1. What is the aim of the US program?| A．To call on people to fight against hunting. |
| B．To reduce the natural areas for human activities. |
| C．To make sure the Mexican wolf population recovers. |
| D．To improve the living conditions of Mexican wolves. |
| A．The US program has achieved great success. |
| B．The baby wolves have faced some difficulties. |
| C．The number of wolves has been out of control. |
| D．The Mexican wolves have trouble fitting into the wild. |
| A．Most young wolves are healthier than adult wolves. |
| B．Wildlife managers should take measures to manage wolves. |
| C．Releasing wolves in the wild causes some environmental problems. |
| D．Mixing human-raised baby wolves with wild wolves benefits them all. |
| A．Wild Mexican wolves are short of food. |
| B．Farmers suffer losses due to increasing wolves. |
| C．Farmers fail to know how to drive away wild wolves. |
| D．Wild Mexican wolves are still in danger of dying out. |
6 . Our two-year investigation into caged (关在笼中) tigers in America sent us through 32 US states—with some truly shocking experiences. But as the deadline neared, I still needed a powerful and hopeful image.
When we began our reporting in 2017—Sharon, writing; me taking photos; and our son, NickRuggia, filming—more tigers likely lived in cages in the US than remained in the wild. The number ranged from 5,000 to 10,000, but without strict government oversight, no one knew for sure.
Roadside zoos that allowed tourists to take pictures of young tigers were the main cause of what’s been called a US tiger crisis (危机). Caged cats often ended up in the illegal wildlife trade. Young tigers, parted from their mothers at birth, were fed poorly and touched by hundreds of people. When they grew too big and dangerous to pet at around 12 weeks, young tigers were put on show, or simply disappeared.
While we documented the unpleasant part of this industry, we also wanted to show the good life these impressive animals could have. With two weeks left before my deadline, I headed to the Wild Animal Sanctuary near Denver, where well-cared cats walked freely in their habitat.
There I met Clay, Daniel, and Enzo, three of 39 tigers rescued from an animal park in Oklahoma. These nearly grown cats raced beside our car, which I’d seen only in the wild. It was a hot July day and soon two of the cats jumped into a pool to cool off. The third rested beside them on the ground. I crossed the road to take a picture of them. Then quietly, I came up close, trying not to disturb (打扰) them. I had the shot.
1. Why did the author start her reporting?| A．To dig out the dark truth of caged tigers. | B．To explore the amazing land in the country. |
| C．To tell people that baby tigers are harmless. | D．To share the happy moment during the trip. |
| A．Forest fires. | B．Climate change. | C．Roadside zoos. | D．Water pollution. |
| A．They prefer to stay indoors. | B．They are badly treated. |
| C．They get used to the changes. | D．They are traded legally. |
| A．To praise her family for their effort. | B．To explain what the animals suffered. |
| C．To introduce a special kind of tigers. | D．To show some tigers lead an easy life. |
7 . A blue hole is a special kind of underwater cave found inland or in the sea, which forms when the earth above a cave falls in and water fills the space.
An inland blue hole’s water is very still and has different layers. A layer of fresh rainwater floats on top of salt water; the fresh water keeps oxygen from the atmosphere from reaching the salt water; brightly colored bacteria live where the two layers meet.
Diving into blue holes is very dangerous. Near the top of the blue hole, there is a layer of toxic gas, which causes itching, headache, and—in large amounts—death. Divers must also be fast. They have to get in and out of a cave before their oxygen runs out. Additionally, divers have to follow a guideline as they swim through a blue hole because it is very dark inside. Without the guideline, they may get lost.
If blue holes are so dangerous, why do explorers and scientists risk their lives to explore them? The reason is that these underwater caves can provide valuable scientific information. They provide clues about geology, archaeology, and biology. For example, some blue hole creatures probably haven’t changed for millions of years.
The blue holes could even provide clues about astrobiology. For example, divers have found bacteria there that can live without oxygen. Astrobiologist Kevin Hand says the bacteria may be similar to forms of life that might exist on Jupiter’s fourth largest moon, Europa. “Our study of life’s extremes on Earth,” he says, can help increase “our understanding of habitable environments off Earth.”
In addition, the oxygen-free environment of the blue holes preserves bones of humans and animals that fell into the caves long ago. By studying blue holes, we can understand what life was like in prehistoric times. As cave diver Kenny Broad says, “I can think of no other environment on Earth that is so challenging to explore and gives us back so much scientifically.”
1. What’s the main idea of Paragraph 1?| A．The definition of a blue hole. | B．The location of a blue hole. |
| C．The formation of a blue hole. | D．The structure of a blue hole. |
| A．In the saltwater layer. |
| B．In the freshwater layer. |
| C．In between the freshwater and saltwater layers. |
| D．In both of the freshwater and saltwater layers. |
| A．The study of life on Earth. |
| B．The study of life in the universe. |
| C．The study of life in prehistoric times. |
| D．The study of life in oxygen-free environment. |
| A．They’re oxygen-free and lifeless. | B．They’re free of air and light. |
| C．They’re death zones and mysterious. | D．They’re poisonous and dark. |
8 . My photographs are the items I would definitely take or guard in case of an emergency. But what else? This was the question I asked myself as a
Unlike some friends and
Because when you hear the roar of the winds, or when something
As
Months and years after the hurricane, I often told people that there are two parts to
But we will do it,
| A．flood | B．drought | C．wildfire | D．hurricane |
| A．hosts | B．partners | C．relatives | D．architects |
| A．applying | B．packing | C．exchanging | D．delivering |
| A．sign | B．gap | C．clue | D．summary |
| A．kit | B．gym | C．space | D．greenhouse |
| A．rests | B．erupts | C．carves | D．cracks |
| A．cheap | B．expensive | C．graceful | D．economic |
| A．destruction | B．appreciation | C．challenge | D．determination |
| A．as usual | B．as follows | C．as scheduled | D．as promised |
| A．annoyed | B．amazed | C．confused | D．frightened |
| A．escaped | B．protested | C．identified | D．processed |
| A．causing | B．preventing | C．surviving | D．suffering |
| A．cutting out | B．putting back | C．giving up | D．working out |
| A．devotedly | B．creatively | C．individually | D．dependently |
| A．in favor of | B．in times of | C．in need of | D．in search of |
9 . Flood (洪水) Safety Guidelines (指南)
Flood (洪水) is one of the most dangerous natural disasters. It may come suddenly and sweep away (冲走) everything. It is important to learn some safety guidelines and get prepared for a flood, especially for those living near a river.
Things to do before a flood
●Move to a safe place immediately if there is an order. Prepare enough food and clean water.
Remember to prepare a first aid kit (急救箱).
Try to move to a place high enough to keep clear of floodwater. Hold to a tree or a woodblock if you are in water. Keep away from electricity.
Things not to do during a flood
Do not take too many personal things with you.
Although flood is dangerous,
| A．never give up hope |
| B．Things to do during a flood |
| C．Here are some tips on flood safety |
| D．Do not drink floodwater because it is not clean |
| E．Listen to the weather warnings (警告) firstly |
10 . Endangered polar bears are breeding (繁殖) with grizzly bears (灰熊), creating “pizzly” bears, which is being driven by climate change, scientists say.
As the world warms and Arctic sea ice thins, starving polar bears are being forced ever further south, where they meet grizzlies, whose ranges are expanding northwards. And with that growing contact between the two come increasing hybrids (杂交种).
With characteristics that could give the hybrids an advantage in warming northern habitats, some scientists guess that they could be here to stay. “Usually, hybrids aren’t better suited to their environments than their parents, but these hybrids are able to search for a broader range of food sources,” Larisa DeSantis, an associate professor of biological sciences at Vanderbilt University, told Live Science.
The rise of “pizzly” bears appears with polar bears’ decline: their numbers are estimated to decrease by more than 30% in the next 30 years. This sudden fall is linked partly to “pizzly” bears taking up polar bears’ ranges, where they outcompete them, but also to polar bears’ highly specialized diets.
“Polar bears mainly consumed soft foods even during the Medieval Warm Period, a previous period of rapid warming,” DeSantis said, referring to fat meals such as seals. “Although all of these starving polar bears are trying to find alternative food sources, like seabird eggs, it could be a tipping point for their survival.” Actually, the calories they gain from these sources do not balance out those they burn from searching for them. This could result in a habitat ready for the hybrids to move in and take over, leading to a loss in biodiversity if polar bears are replaced.
“We’re having massive impacts with climate change on species,” DeSantis said. “The polar bear is telling us how bad things are. In some sense, “pizzly” bears could be a sad but necessary compromise given current warming trends.”
1. Why do polar bears move further south?| A．To create hybrids. | B．To expand territory. |
| C．To relieve hunger. | D．To contact grizzlies. |
| A．Broader habitats. | B．More food options. |
| C．Climate preference. | D．Improved breeding ability. |
| A．A rare chance. | B．A critical stage. |
| C．A positive factor. | D．A constant change. |
| A．Polar bears are changing diets for climate change. |
| B．Polar bears have already adjusted to climate change. |
| C．“Pizzly” bears are on the rise because of global warming. |
| D．“Pizzly”bears have replaced polar bears for global warming. |
