Many of us remember being in awe(敬畏) when we saw cloned dinosaurs running wild in the film Jurassic Park. And the idea of using technology to revive(恢复) extinct species has long fascinated not only writers and directors, but scientists as well.

According to The Telegraph, woolly mammoths(长毛猛犸象), which featured in the popular Ice Age animated movie series, “may walk the earth once more” now that scientists have taken another step toward realizing a long-held dream—recreating their DNA.

Mammoths became extinct around 10,000 years ago. However, since the discovery of near-perfect preserved remains in Arctic permafrost(北极冻土带) in May 2013, a variety of research studies have been carried out since.

Geneticists from Harvard University analyzed DNA from the remains, looking for genes which separated mammoths from elephants, such as hairiness and ear size. They then used the results to reproduce exact copies of 14 mammoth genes. “It is the first time that mammoth genes have been alive—although so far it has only been done in the lab,” George Church, lead researcher of the project, told the Sunday Times.

Church then used a new technique which allows scientists to edit DNA carefully, replacing sections of elephant DNA with the mammoth genes. So “we now have functioning elephant cells with mammoth DNA in them,” he said.

However, Church ruled out the possibility of bringing the mammoths back to life via cloning from frozen remains. He said he “preferred to focus on rebuilding the full mammoth genome(基因组) by analyzing DNA from preserved remains and putting it into the cells of its closest living relative – the Asian elephant,” reported The Telegraph.

Church argued that the return of the woolly mammoth—or rather, the return of something very similar—could help bring back fragile(脆弱的) ecosystems. However, some scientists believe that bringing back the mammoth would be unethical.

Professor Alex Greenwood, an expert on ancient DNA, said: “We may face the extinction of African and Asian elephants. Why bring back another elephant from extinction when we cannot even keep the ones that are not extinct around?” he told the Sunday Times. “What is the message? We can be as irresponsible with the environment as we want. Then we’ll just clone things back?”

“Money would be better spent focusing on conserving what we do have than spending it on an animal that has been extinct for thousands of years,” he said.

1.We can learn from the article that ______.

A. cloned mammoths followed cloned dinosaurs to get revived

B. the technology to revive mammoth genes is already mature

C. George Church and his colleagues tried to reproduce mammoth DNA

D. Church and his team managed to list all the genes that separate mammoths from elephants

2.According to Church, what is the significance of his study?

A. It could help prevent the extinction of the Asian elephant.

B. It could help people better tell elephant DNA from mammoth genes.

C. It could help bring back some extinct species and save fragile ecosystems.

D. It could help bring mammoths back to life via cloning from frozen remains.

3.The underlined word “unethical” in Paragraph 7 is closest in meaning to ______.

A. unacceptable B. misled

C. impractical D. illegal

4.According to the article, Professor Alex Greenwood believes that _______.

A. there is no need to worry about the extinction of African and Asian elephants at present

B. it’s necessary to bring back species that are beneficial to human beings from extinction

C. the return of the woolly mammoth would help to balance ecosystems

D. it’s more important to protect present species than to bring back extinct ones

One day, during the long summer holiday, Mrs. Martins took Brendon and his younger brother Kim to the beach. As soon as they got there, the two children _______ down to the sea to try out their new surfboards(冲浪板). They were soon swimming out to the _____ and riding back on their boards.

After a while, Brendon noticed that Kim was ____ away from him.

“Come back, Kim,” he shouted. “Mum said we have to stick together.” Kim put his arms over the side of his board and began paddling (划水) , but _____ getting closer, he began moving further away.

“Brendon, help!” called the young boy. “I’m ____ in a rip current (离岸流).” Brendon quickly paddled over to his _____.

“____ the back of my board and I’ll pull you to the beach,” he told the ____ boy. But the rip was too ______ and soon both Brendon and Kim were moving further from the beach.

“I can’t ____ see our beach any more,” cried Kim.

“Yes, but we’re not moving out of the sea any more. We’re just floating along the coast. See, there’s the next beach.” said Brendon ____. “We’re moving closer to it.” Sure enough, the current was now taking them closer to the beach and becoming_____.

“Right, it’s time to paddle,” said Brendon, suddenly full of ____.

Before long the children paddled to the beach _____ they sat for a few moments to _______ their breath. After a while, they_____ up their boards and started the long walk back to their mother. When they got there, they were _______ to find the beach full of people and boats.

“Thank goodness!” cried their mother running to _________ them. “We were just about to start a search. One minute you were in the waves in front of me and the next you were gone. I was so_____.”

“It’s OK,” said Brendon, hugging his mother. “We did just as you told us and ______ together.”

1.A. rushed B. got C. came D. jumped

2.A. beaches B. waves C. fields D. sands

3.A. turning B. breaking C. floating D. pulling

4.A. because of B. in addition to C. in case of D. instead of

5.A. found B. caught C. stricken D. rested

6.A. mother B. sister C. friend D. brother

7.A. Hold onto B. Put down C. Hold up D. Take off

8.A. determined B. frightened C. concerned D. excited

9.A. hard B. deep C. strong D. soft

10.A. still B. already C. hardly D. even

11.A. carefully B. sadly C. cheerfully D. eagerly

12.A. weaker B. clearer C. lower D. faster

13.A. spirit B. energy C. power D. force

14.A. how B. why C. where D. when

15.A. save B. feel C. hold D. catch

16.A. picked B. mixed C. rolled D. fixed

17.A. angry B. anxious C. hurried D. surprised

18.A. punish B. beat C. hug D. praise

19.A. disappointed B. worried C. embarrassed D. amazed

20.A. stuck B. shouted C. shook D. swam

It was one of my first lessons as an international student in New York City. My US history teacher had just finished his lesson. He sat back in his armchair comfortably, and asked: “Was there anybody doing anything interesting yesterday?”

“I drew a panda, which was lovely!” a girl beside me shouted.Then, the talk developed rapidly. Someone said he had received his learner’s driving permit, while another mentioned that she had spent the first salary from her part-time job. Everybody seemed to have something to say. Although there was a range of people, from different backgrounds, people seemed to feel at home with each other.

Not me. I stayed aloof from the discussion. I looked through my notes until I looked up to see another teacher come in and share some cookies he had made yesterday. The beautifully baked cookies sent out a good smell, which made it impossible to concentrate on my work any longer. However, my seat was in the back row, and I was too shy to stand up and take a cookie for myself.

“Go ahead and have one!” It was the history teacher: “If you don’t stand up, nobody is going to feed you!”

I was still hesitant, but I got up and took a cookie with some other classmates. Now I felt more at ease. We laughed about how “greedy” we were.

The “cookie crisis” had taught me a lesson. I would have to be less shy in the United States. Here was a mixed and various culture, and if I wanted to get anywhere I would have to brave its newness and difference and make myself heard, just as the teacher had said. Otherwise, “Nobody is going to feed you.” It was something a person new to the US, such as myself, needed to learn.

1.The atmosphere in a US classroom is quite __________.

A. lively B. lonely

C. bad D. quiet

2.What does the underlined phrase “aloof from” mean?

A. in spite of B. instead of

C. apart from D. away from

3.What prevented the writer from getting a cookie for himself at first?

A. His bravery. B. His shyness.

C. His strangeness. D. His weakness.

4.The “cookie crisis” in the last paragraph was __________ to the writer.

A. an important problem B. a kind of valuable food

C. a turning point in his life attitude D. a dream in his school life

Monday 2nd January

I am in a small village in the Carpathian Mountains, north of Bucharest, the capital of Romania. I’ve come to see the brown bears, which come to the villages at night to look for food. They walk 20 kilometres a night to get here. A farmer told me that some of his sheep have been killed by bears. But this is unusual. Usually, the bears just take bits of food which people have thrown away. Tonight I hope I’ll see them.

Tuesday 3rd January

Last night I waited with a group of tourists and as it grew dark, we saw the huge black shapes of bears. It seems the bears don’t go for people, unless they are attacked first. They were not afraid of the tourists, who took photos of them. Those clever bears knew where to go for their dinner. They jumped straight into the rubbish, where there was lots of food which people had thrown away.

Wednesday 4th January

Although it’s wonderful to see the bears in the village, it can only mean one thing: their habitat is disappearing. They would prefer to stay hidden in the mountain forests, but the trees have been cut down for firewood. So they cannot find enough food any more.

Thursday 5th January

Today I met the head of the Carpathian Animal Protection Group. He says that there are only about 2,500 bears left, and is worried that they will soon become extinct. Rich people from other countries pay a lot of money to come and shoot the bears for sport. The poor people from these villages need the money. But perhaps they could make more money from the tourists who want to come just watch the bears; and this would continue in the future. Once the bears are all dead, the tourists will stop visiting the village. But if the bears keep visiting the villages, then, perhaps, so will the tourists.

1.The best title for this passage would be _____________.

A. Hungry Brown Bears B. Brown Bears in the Forest

C. Wandering Brown Bears D. Brown Bears—A Wonder

2.It is unusual to the writer that ________________.

A. the brown bears like to be taken photos of.

B. the bears come out at night to look for food

C. the bears just take bits of food thrown away

D. the bears have attacked a farmer’s sheep

3.The villagers could continue to earn money from the bears if _________.

A. they shot the bears for sport

B. people paid more money to kill them

C. more tourists came to see the bears

D. the villagers sold the bears’ skins to tourists

4.What will happen to the bears in the future?

A. They may be kept in zoos.

B. They may become extinct.

C. They may keep eating rubbish.

D. They may be watched by visitors.

Sun Tours: Short breaks in New York

DAY 1: TIMES SQUARE AND THE LINCOLN CENTER

Welcome to New York—the Big Apple! Here in New York the wonders of the Big Apple exceed (超出) all expectations—the fantastic skyline, wonderful restaurants, theaters, museums, shops and attractions. On your first day you will visit the famous Lincoln and Rockefeller Centers, and drive down Fifth Avenue. You will drive through Times Square, the “Crossroads of the World”. You will then travel to Central Park, a miracle in the center of Manhattan. Lunch is on your own, but this evening you will have dinner at the famous Jekyll and Hyde club, where the waiters are all dressed as vampires(吸血鬼), and at some point in the evening Frankenstein (科学怪人)comes to life.

DAY 2: EXPLORING THE CITY

The entire day is yours for sightseeing and shopping. Explore the attractive city of New York with its skyscrapers, bridges, historic landmarks and Broadway theaters.

DAY 3: DOWNTOWN AND SOUTH STREET SEAPORT

Today you will visit Greenwich Village, Wall Street and the World Trade Center. You will visit South Street Seaport, a 19th-century seaport with narrow streets, hundreds of shops, an international food stand and street entertainment. This afternoon you will visit Chinatown, and finally the Empire State Building Observatory, which towers 1,250 feet above New York City. You will use the high-speed elevators to go to the top, unlike King Kong who climbed up the outside of the building. This evening, you will have dinner at the well-known Tavern-on-the-Green restaurant overlooking Central Park.

ARRIVING IN NEW YORK

A Sun Tours representative will meet you at JFK airport and take you to your hotel, which is in the center of the city. When you check in, you will receive further information about this evening’s “Getting-to know-each-other” party at the Manhattan Restaurant.

1.If you want to join in this tour, which of the following will you contact?

A. Sun Tours B. Hyde Club

C. Greenwich Village D. JFK Airport

2.How many places will you visit on the third day?

A. Five B. Six

C. Seven D. Eight

3.What can we know from the last paragraph?

A. You will go to the hotel in the center of the city by yourself.

B. When you arrive at the airport, you will be told about the tour plan.

C. You have known all about the Manhattan Restaurant before your arrival.

D. When you check in, you will know more about the evening party.

If you say, “The cat’s out of the bag” instead of “The secret is given away,” you’re using an idiom. The meaning of an idiom is different from the actual meaning of the words used. “An apple a day keeps the doctor away” is a proverb. Proverbs are old but familiar sayings that usually give advice. Both idioms and proverbs are part of our daily expressions. Many are very old and have interesting histories. See how many of these expressions you know.

“Bury the hatchet.”

Native Americans used to bury weapons to show that fighting had ended and enemies were now at peace. Today, the idiom means to make up with a friend after an argument of fight.

“A close shave.”

In the past, student barbers learned to shave on customers. If they shaved too close, their customers might be cut or even hardly escape serious injury. Today, we use the idiom if a person narrowly escapes disaster.

“Raining cats and dogs.”

In Norse mythology the dog is associated with wind and the cat with storms. This expression means it’s raining very heavily.

To “shed crocodile tears.”

Crocodiles have a reflex that causes their eyes to tear when they open their mouths. That makes it look as though they are crying while swallowing their food. In fact, neither crocodiles nor people who shed “crocodile” tears feel sorry for their actions.

“Saved by the bell.”

In 17th-century England, a guard at Windsor Castle was accused of falling asleep at his post. He claimed he was wrongly accused and could prove it; he had heard the church bell chime (鸣响) thirteen times at midnight. Townspeople supported his claim and he was saved. Today we think of the bell that ends a round in boxing, often saving the boxer from injury, or the bell at the end of a class period, saving you from more work. Now this idiom means rescue from a situation at the last possible moment.

1.The best title of this passage will probably be ___________.

A. Everyday Expressions B. Not Idioms But Proverbs

C. Idioms and proverbs are old D. Idioms or proverbs

2.The purpose of this article is to ________.

A. compare some useful and interesting idioms and proverbs

B. tell us some idioms and proverbs which can be used today

C. explain the meaning of some interesting everyday expressions

D. show the importance of using proverbs and idioms in your writing

3.It can be inferred from the article that _________.

A. idioms and proverbs are a must in our life

B. proverbs are more common than idioms

C. idioms are more interesting than proverbs

D. it is difficult to guess the meaning of idioms

4.Which of these statements is an example of “a close shave”?

A. My brother bought a new computer yesterday.

B. My friend will come to my city to see me.

C. A car nearly hit me on my way to school.

D. No one in my school has ever been to Canada.

 0  143681  143689  143695  143699  143705  143707  143711  143717  143719  143725  143731  143735  143737  143741  143747  143749  143755  143759  143761  143765  143767  143771  143773  143775  143776  143777  143779  143780  143781  143783  143785  143789  143791  143795  143797  143801  143807  143809  143815  143819  143821  143825  143831  143837  143839  143845  143849  143851  143857  143861  143867  143875  151629 

违法和不良信息举报电话:027-86699610 举报邮箱:58377363@163.com

精英家教网