外研版（2019）高中英语必修1：Unit 5 Into the wild 单元过关测试

    Sea urchins (海胆) are small creatures, but what's really remarkable about them is that they eat anything that happens to float by. They have really sharp teeth they use to rid rocks of algae (海澡), which makes them pretty valuable especially in places like Hawaii where algae are threatening the coral reefs. In the summer of 2019, 500,000 of them were used to deal with the algae.

    The problem started when non-native algae were introduced to the ecosystem of Kane' ohe Bay in the 1970s. Because they had no enemies, they ended up taking over the bay, according to the National Marine Fisheries Service (NMFS). The algae blocked sunlight from reaching the coral, which in turn affected the local fish because they changed the chemistry of the water.

    That's when the NMFS turned to sea urchins that loved to devour the algae. But they had to grow to the size of a cherry tomato before they could be used. Since 2011, sea urchins have been grown and used to handle the algae problem. Some of the funds are available due to an unfortunate incident.

    In 2005, a ship was grounded on a shallow reef near Kane' ohe Bay. When the ship was removed, 20 acres of reefs have been damaged. When there is environmental damage, the NMFS and other agencies receive funds from the wrongdoers and the funds are used to restore the damage. Some funds were spent on other projects like the sea urchins. When they are large enough, divers carefully place them on the reef.

    Algae isn't the only thing that threatens the coral reefs. Climate change and the effects of fishing and tourism in the area also endanger the coral reefs. But turning to sea urchins instead of man-made solutions seems like the best way to go.

Researchers have discovered a new bacterium that feeds on polyurethane, a kind of plastic that is difficult to recycle or destroy. Scientists say the discovery could help reduce a flood of hard-to-recycle plastics that are ending up in the world's landfills (垃圾填埋地) and polluting oceans.

A team from the Helmholtz Center for Environmental Research in Leipzig, Germany, found the new type of soil bacteria. It was spotted in an area that contained a large amount of plastic waste. The team discovered the bacteria were feeding on polyurethane diol, which was widely used in many different products.

One problem is that recycling polyurethane requires a lot of energy. The plastic material does not melt when heated. Most polyurethane-based products end up in landfills, where they can release dangerous chemicals. The team round that the bacterium can produce enzymes (酶) that eat away polyurethane. This would make it possible to break down the material in the environment. The results were recently reported in a study in the publication Frontiers in Microbiology. Hermann Heipieper helped write the report. He said in a statement the finding “represents an important step in being able to reuse polyurethane products.”

German study noted that plastic-eating bacteria could be easily controlled and produced for industrial use. The researchers said the next step is to find more information about the bacterial enzymes that can break down polyurethane.

Scientist Douglas Rader wrote about the issue in a 2018 article for the Environmental Defense Fund. He said much more study should be carried out to learn about the complex relationships between bacteria and marine ecosystems. "Such research is needed before we can take action such as putting plastic-eating bacteria into the ocean," Rader wrote.

As an educator and health care provider, I have worked with numerous children infected with the virus that causes AIDS. The relationships that I have had with these special kids have been gifts in my life. They have taught me so many things, but I have especially learned that great courage can be found in the smallest of packages. Let me tell you about Tyler.

Tyler was born infected with HIV: his mother was also infected. From the very beginning of his life, he was dependent on medications to enable him to survive. When he was five, he had a tube inserted (插入) in a vein in his chest. This tube was connected to a pump, which he carried in a small backpack on his back. Medications were linked to this pump and were continuously supplied through this tube to his bloodstream. At times, he also needed supplemented (补充的) oxygen to support his breathing.

Tyler wasn't willing to give up one single moment of his childhood to this deadly disease. It was not unusual to find him playing and racing around his backyard, wearing his medicine-laden backpack and dragging his tank of oxygen behind him in his little wagon. All of us who knew Tyler were amazed at his pure joy in being alive and the energy it gave him. Tyler's mom often teased him by telling him that he moved so fast that she needed to dress him in red. That way, when she peered through the window to check on him playing in the yard, she could quickly spot him.

This dreaded disease eventually wore down even the likes of a little dynamo like Tyler. He grew quite ill and, unfortunately, so did his HIV-infected mother. When it became apparent that he wasn't going to survive, Tyler's mom talked to him about death. She comforted him by telling Tyler that she was dying too, and that she would be with him soon in heaven.

A few days before his death, Tyler called me over to his hospital bed and whispered, "I might die soon. I'm not scared. When I die, please dress me in red. Mom promised she's coming to heaven, too. I'll be playing when she gets there, and I want to make sure she can find me."

When our Scottish puppy reached doggie adolescence, she suddenly stopped obeying my commands. Previously, if I called "come," Annie would fly across our yard to my arms. Now, the 8-month-old gave me an aggressive "make me" look and ran the other way.

Our dog trainer advised us to stop complaining. "She's a teenager," she said. Now, a new study is backing that up: Dogs, it says, experience an oversensitive period just like human teenagers. "There is abundant folk knowledge that the behavior of adolescents differs from younger or older dogs," says Barbara Smuts.

Puppies bond with humans much as children do. "But owners often feel like they're failing when their puppies reach adolescence," about 8 months for most dogs, says Lucy Asher. Like teenagers, adolescent dogs can disregard and disobey their owners. Indeed, teenage dogs are the most likely age group to land in U.S. shelters.

To see exactly how adolescence changes dog behavior, Asher and her team monitored 70 female dogs being raised as potential guide dogs. They asked caregivers to score the puppies on separation-related behaviors, like trembling when left behind. Dogs with high scores on this behavior entered adolescence earlier-at about 5 months, compared with 8 months for those with lower scores. Various factors cause human teenage girls with poor parental relationships to also enter adolescence at a younger age. Thus, similar to humans, dogs that have bad relationships with their caregivers see changes in their development.

According to Smuts, adolescent dogs that were stressed by separation from their caregiver also increasingly disobeyed that person, showing the insecurity of human teenagers.

Because of the similarity between adolescent pups and humans, dogs can serve as a model species for studying adolescence in humans, the scientists say. The temporary nature of dogs which disobey the owners may make us worry less when our pups suddenly get minds of their own.

Whoever wrote the song "It's the Most Wonderful Time of the Year" must have never experienced holiday blues. Fortunately, psychological research suggests some effective ways you can beat the holiday blues. The key point is that sadness and other tough emotions are not what we should try to avoid. . Here are four strategies to help you make your own happiness recipe this holiday season.

Don't force cheer

At family gatherings with cousins you secretly can't stand, you tend to put on a happy face. Indeed, that might even seem like the most mature response—no drama, no conflict. But a 2011 study followed dozens of bus drivers, looking to see when they gave forced or honest smiles at their passengers. The results showed when the drivers pretended to have a good mood, their actual moods got worse. .

Let off sadness

The results of the bus­driver study can be explained by researchers, who find that negative feelings like sadness or anger only increase when we try to control them. . We don't like contradictory behavior.

Respond cautiously

Recently, scientists have been paying special attention to the benefits of caution. When you respond cautiously to an emotional trigger (e.g.overcooking the holiday turkey), you pause rather than reacting at once. . Besides, it is associated with less anxiety, and may even carry physiological benefits.

Of course, the holidays will bring a mix of highs and lows, but the most important lesson to keep in mind is that this variety of emotions might be the best thing possible for your overall well­being. In other words, sadness, anger, and other difficult emotions are nothing to fear. Just make sure you're balancing them with lighter experiences. And don't forget to give yourself a break.

A. Relax your mind

B. Enjoy a mix of emotions

C. We tend to deny the important function emotions serve

D. Instead, they can help contribute to a healthy and happy life

E. So trying to force happiness seems to have the opposite effects

F. A cautious response to a negative event reduces sadness we experience

G. We feel bad when our appearance contradicts how we truly feel inside

Last summer I moved to Kirkland to live with my fiancé, giving up being a lawyer. Without a job, I spent my days aimlessly wandering around my new neighborhood.

That's how I1Steve. I'd seen him plenty of times before—untidy, with a messy gray beard, 2 a worn cardboard sign at the street corner. His 3 asked for help with food or rent—nothing fancy, and never for alcohol or drugs. Having lived in the area for ten years, Steve was well known to the locals. Even as I chatted with him, several people waved to him as they went by. I 4called him the Mayor of Kirkland. He laughed, saying he hoped the name would stick. He had much to do before his term was 5.

In September, he told me he'd been homeless because he had a legal issue for the last thirty years and, as a result, his social security 6 had been halved. The remaining amount wasn't enough to live on, so he was forced to spend his days trying to 7 the difference.

Knowing I had legal experience, he asked me if I could help him with this matter. I agreed 8. In the months that followed, I began to 9 more time and energy into his case. When we met to discuss his case, it was as if a heavy 10 was lifting off his back. I could sense his growing optimism. He started describing me as his "little ray of 11" and telling his friends what a great 12 I was doing.

Then came the day when the court finally decided to 13 most of what Steve owed, which meant he would have enough money to get his life back on 14. I could see tears in Steve's eyes when he heard the 15. But it also meant that I wouldn't see him as often anymore. When I told Steve this, he grinned with tears in his eyes," We're friends, and friends make time to see each other. Besides, the mayor's still got to do his rounds."

Astronauts have traditionally been serious, sensible types with the "right stuff" who can (trust) to fly equipment. But any mission to Mars will need a "joker" or "class clown" figure to be (success), according to NASA research. A sense of humor will be vital for any team to keep morale (士气) high on a two­year trip to Mars may happen in the 2030s.

According to researchers, groups work best when they have a "joker" who has the ability to pull everyone together, bridge gaps when tensions appear really boost morale. When astronauts are in a confined space on a mission to Mars, tensions are likely (occur). It's vital that there should be one who can help everyone get along, so they can do their jobs and get there and back (safe).

Researchers have studied isolated groups of people in extreme environments including Russian, Chinese, Indian and Polish (explorer) based in Antarctica. Norwegian explorer Roald Amundsen succeeded while Captain Scott (fail) to reach the South Pole because the Norwegians had a "clown" figure on their team. He laughed and was very happy, (keep) up people's spirits.

But researchers added: "Being funny won't be enough to land somebody the job. He also needs to be excellent scientist and engineer and be able to pass a strict training programme."

An 80-year-old man was sitting on the sofa in his house along with his 45-year-old highly educated son. Suddenly a crow perched on their window.

The father asked his son, "What is this？"The son replied, "It is a crow. "

After a few minutes, the father asked his son for the second time, "What is this？"The son said, "Father, I have just now told you, it's a crow!"

After a little while, the old father again asked his son for the third time, "What is this？"

At this time some expression of irritation was felt in the son's tone when he said to his father with a rebuff. "It's a crow, a crow. "A little while later, the father again asked his son the fourth time, "What is this？"

This time, the son shouted at his father, "Why do you keep asking me the same question again and again, although I have told you so many times' IT IS A CROW'. Are you not able to understand this？"

A little later the father went to his room and came back with an old tattered diary, which he had maintained since his son was born. On opening a page, he asked his son to read that page. When the son read it, the following words were written in the diary：

注意：

1）所续写短文的词数应为150左右；

2）至少使用5个短文中有下划线的关键词语；

3）续写部分分为两段，每段的开头语已为你写好；

4）续写完成后，请用下划线标出你所使用的关键词语。

Today my little son aged three was sitting with me on the sofa,

……

After reading the diary,