1 . Desertification, the process by which fertile (肥沃的) land becomes desert, has severe impacts on food production and is worsened by climate change.
Africa’s Great Green Wall is a project to build an 8,000- kilometre-long forest across 11 of the continent s countries. The project is meant to contain the growing Sahara Desert and fight climate change.
First proposed in 2005, the project aims to plant a forest from Senegal on the Atlantic Ocean in western Africa to Eritrea, Ethiopia and Djibouti in the east.
| A．But the project faces many problems. |
| B．That is only 4 percent of the programme’s goal. |
| C．However, it is difficult to work on the Great Green Wall. |
| D．A quarter of Africa is under threat of food shortage. |
| E．Some progress has been made in recent years in the east of the continent. |
| F．Supporters hope that the project will create millions of green jobs in rural Africa. |
| G．The U.N. says up to 45 percent of Africa’s land is impacted by desertification, worse than any other continent. |
Welcome to Shangri-La (香格里拉) . Although located in Yunnan, it has many old
“I just made it to the South Pole!”
Meet Harpreet Kaur Chandi, also known as Polar Preet, the 33-year-old who has been making headlines all over the world after
“The reason
As a part of her tough expedition, Preet endured temperatures as low as minus 50 degrees Celsius, and wind speeds of up to 96 kilometers per hour. She
“It was generally windy, and there were only two
Despite all the hardships and challenges, Preet says that there’s no stopping and that she has started training for
4 . Around the world, people are realizing the significant problems caused by plastic waste. In the last 65 years, we have become increasingly dependent on plastic. It’s easy to understand why: it’s cheap to produce, light — therefore easy and cheap to transport — and incredibly strong and durable.
One popular solution to the problem is to prohibit single use plastics. In the British supermarkets, shoppers are encouraged to make more environmentally-friendly choices in packing and transporting their food.
However, such plans may not be beneficial to eliminate (消除) the use of single-use plastic altogether.
Another issue is that alternative materials to plastic are often more environmentally harmful than plastic. Take paper bags, for example.
Clearly there is a need to reduce plastic waste and its impact on the environment.
| A．But it’s these advantages that also make it so harmful. |
| B．They are very fragile and rarely reusable, unlike plastic. |
| C．One of the fields where single-use plastic has a vital role is medicine. |
| D．However, simply banning their single use may not be the best option. |
| E．It also boosts the local economy and save costs in managing littering and waste. |
| F．Bans on single-use plastic items like drinking straws are also coming into place. |
| G．According to a research, they require four times more energy when produced than a plastic bag. |
5 . What Is Your Pet Trying to Tell You
Animals want our attention, and sometimes they’re quite obviously about asking for it. Unusual behaviors are often our pets’ way of telling us to stop what we’re doing and play with them. It’s why Fido constantly chases his tail and why Kitty keeps rolling around. A desperately bored pet may have “bad” behaviors to get a reaction-even a negative one!
Feed me.
Sure, your dog loves you, but that’s not why he’s licking(舔)your face. A puppy learns to lick his mother’s mouth to get a little leftover food, so Spot isn’t kissing you in our sense of the word; he just wants a snack.
I’m stressed.
Cat owners also misinterpret their furry friends’ kisses. While a cat might lick you to show love, sometimes she’ll do it to ease herself. One way to tell if her licking is stress-related is to see if it goes on for an extended period of time. Birds also overclean when they feel anxious. Some will even drag out their own feathers.
My tail tells all.
Dogs wag(摇)their tails to the right when they see something or someone they want to approach, and to the left when they see something they want to avoid. When frightened, dogs curl their tails in, while cats wrap theirs around themselves. And if a cat’s tail looks like a question mark, she’s eager to play.
1. What does a dog show if it kisses its owner?| A．Hunger. | B．Love. | C．Fear. | D．Sadness. |
| A．Two. | B．Three. | C．Four. | D．Five. |
| A．They will drag others’ feathers. |
| B．They will approach someone they like. |
| C．They will clean their feathers more than necessary. |
| D．They will stare at their owners for a longer time. |
6 . Fish genetically engineered to glow blue, green, or red under blacklight have been a big hit among aquarium lovers for years. But the fluorescent (发荧光的) pet is not restricted to glass displays anymore. The red-and-green-glowing versions, more vivid than normal zebrafish even in natural light, have escaped fish farms in southeastern Brazil and are multiplying (繁殖) in creeks in the Atlantic Forest, a new study shows. It is a rare example of a transgenic animal accidentally becoming established in nature, and a concern for biologists, who worry the transgenic fish could threaten the local fauna (动物群) in one of the most bio-diverse spots on the planet.
In the 2000s, companies saw the potential of the fish as pets. Trademarked as Glofish, they became the world’s first genetically engineered species to be commercially available. Now, they are one of the first to escape and thrive in nature. Early on, environmentalists worried about the possibility, and Glofish sales were banned in some U. S. states such as California and several countries-including Brazil. In 2014, a single Glofish was spotted in canals of Florida. But it had not multiplied, probably because native predators such as the eastern mosquitofish and the largemouth bass ate the intruder, said the biologist who spotted the fish, Quenton Tuckett. Unlike Florida, Glofish thrived in the Brazilian creeks. In 2017 he and colleagues began to survey five creeks in three cities, finding transgenic zebrafish in all of them.
The Glofish are reproducing all year round, with a peak during the rainy season — just as native zebrafish do in Asia. But the transgenic fish seem to achieve sexual maturity earlier than their forebears, which allows them to reproduce more and spread faster. The invaders are also eating well: a diversified diet of native insects, algae, and zooplankton.
Despite Brazil’s ban on sales of the fish, stores all over the country sell them as pets. They may soon colonize other parts of the country. Tuckett says it should be “a wake-up call”. For now, the glowing fish “could be considered little weeds growing up out of the concrete”, Tuckett says, but points out that even little weeds can grow to cause a lot of damage.
1. What is the concern of the biologists?| A．The ecological impacts are unpredictable. |
| B．The transgenic fish could do harm to the local animals. |
| C．The transgenic fish accidentally became established in nature. |
| D．The transgenic fish are more vivid than normal zebrafish in natural light. |
| A．They were kept as pets before the 2000s. |
| B．They were prohibited from sales throughout the U. S. |
| C．They didn’t thrive in Florida probably due to the local enemies. |
| D．They were found in all of the Brazilian creeks in 2017. |
| A．The Glofish. | B．The native zebrafish. |
| C．The largemouth bass. | D．The eastern mosquitofish. |
| A．Indifferent. | B．Ambiguous. |
| C．Cautious. | D．Supportive. |
7 . When you garden, you get sunshine, fresh air and exercise.
Pick the right plants. In your containers, you can control the soil and the amount of water, but not the sunlight.
Protect the plants from wind. Wind can damage parts of the plants. It can also dry them out. Choose a location for your garden that has shelter from a building or make your own wind protection.
Water your plants regularly and put the water directly on the soil. It is best to water early in the morning. If you can’t water the plants in the morning, water them in the late afternoon or early evening.
| A．Get the right type of soil |
| B．Grow different plants in the same pot |
| C．Find out which plants can grow in the light conditions you have |
| D．Try not to water the plants during the hottest part of the day |
| E．Working with soil and plants can bring health benefits, too |
| F．Gardening can also produce healthy fruits and vegetables for your family |
| G．Or grouping plants together can protect your plants from being blown off |
8 . Once there was a dandelion (蒲公英) living alone by the road. It felt bored and sad all day as no one ever stopped to take a look at or talk to it.
One day, a mother was walking on the road with her baby. The baby was crying hard and loudly. No matter what the mother did, she couldn’t get the baby to stop crying. Then the mother looked down, and she found the lonely dandelion. It looked so lovely in the sun with its white seeds widely open, and more beautiful than other plants around.
The mother squatted down, (蹲下) picking the dandelion softly. Then she brought it up to her baby so that he could see it clearly. When the baby saw the flowers of the dandelion, he quickly stopped crying and looked at them with interest.
His mom put the dandelion near her mouth and blew the flowers up and down. The dandelion seeds then flew in the air, spreading far away with the wind. The mother gave the dandelion to her son. He didn’t know what the plant was, but he knew it was fun to play with, which made him giggle (咯咯笑) so happily.
Now the dandelion knew its value and didn’t feel sad. It lived a beautiful life just by being itself. It wasn’t as beautiful as other flowers, but it brought the child a simple kind of happiness that money can’t buy.
The dandelion’s story tells us that everyone is special and great. We can help others in one way or another. We’re far greater than we think we are.
1. Why did the dandelion feel lonely at first?| A．Because no one noticed it . | B．Because it left its mother. |
| C．Because it lived by the road. | D．Because it had no friends. |
| A．Kind and honest. | B．Friendly and helpful. |
| C．Patient and careful. | D．Beautiful and funny. |
| A．it could travel farther | B．it found its value |
| C．it was powerful again | D．it had more seeds than before |
| A．Great minds think alike. |
| B．Two heads are better than one. |
| C．Rome was not built in a day. |
| D．All things in their being are good for something. |
Despite occupying a relatively small area, rainforests have an important role to play in maintaining the world and they are home to a rich
As the lungs of the planet, rainforests have their own perfect system,
Worryingly, rainforests around the world are disappearing at
10 . Honeybees can’t swim, and when their wings get wet, they can’t fly. But one study shows that honeybees do have another, less obvious choice to save them from death in the water: surfing.
The discovery began with a lucky accident. When research engineer Chris Roh passed by Caltech’s Millikan Pond, he saw a honeybee resting in the water, and since it was midday, the honeybee’s shadow (影子) fell directly on the bottom of the pond. However, what really caught his eye was the waves created by the honeybee’s wings, as the waves from one wing crashed with those from the other wing.
Roh brought honeybees to the lab, where he recreated the conditions, he saw at Mfillikan Pond. He placed a bee in a pan of still water and then shone filtered (过滤的) light from above to pretend it was the midday sun. He did this with 33 bees, but only for a few minutes one single bee at a time, and then gave each bee time to recover.
While water prevents a bee from flying by clinging (紧附) to its wings, the same condition obviously provides another way for the bee to escape. The bee pulls water with its wings, creating waves that can push it forward.
But there are some limitations. Obviously, the bees can’t produce enough force to get them out of the water. However, the wave can push them forward enough to the edge of the water, where they can then climb out and fly away. This behavior is more tiring than flying, and Roh guesses the bees can only hold it for about 10 minutes before using up their strength, so the chances to get out may, be limited.
“This behavior has never been recorded in other insects,” Roh added. This study focused on honeybees, but future studies could investigate whether it is also used by other bee groups or possibly even by other winged insects.
1. According to the new study, what helps honeybees avoid death in water?| A．The crash between their wings. |
| B．The water clinging to their bodies. |
| C．The strong will to get out of water. |
| D．The waves produced by their wings. |
| A．To help the honeybees recover quickly. |
| B．To make the honeybees gain more force. |
| C．To keep the honeybees in warm conditions. |
| D．To create a shadow on the bottom of the pan. |
| A．By using examples. |
| B．By giving explanations. |
| C．By making a comparison. |
| D．By listing specific numbers. |
| A．No insects can surf other than honeybees. |
| B．More methods will be used to study insects. |
| C．Researches will be done into other bee species. |
| D．Bees made more and more scientists concerned. |
