Polar bears have patrolled the planet's icy regions for millions of years longer than previously thought — riding out several episodes of global warming in that time. While this suggests their future might not be so bleak, it does not ensure that they will survive the melting occurring in the polar regions today.An international team of researchers has just completed the most comprehensive analysis yet of the polar bear genome (基因组). The team examined DNA from 23 living polar bears and a 110,000-year-old polar bear jawbone. Aided by comparisons with the genomes of brown and black bears, they found that polar bears first emerged as a separate species between four and five million years ago. Previous studies had suggested the species didn't diverge (分化) from brown bears until much later — perhaps just 600,000 years ago.The analysis also showed that polar and brown bears have sometimes interbred (杂交) since their initial divergence and that populations of polar bears have been changing over the past million years in accordance with the climate. Polar bear numbers dropped during warm periods but soared again with prolonged ice ages — most noticeably during a cooling period between 800,000 and 600,000 years ago. The population looks set to fall again as melting pack ice forces polar bears back to the land-based habitats (栖息地) of brown bears, where interbreeding has recently been observed. Should extensive interbreeding occur, both polar and brown bear populations could decline with the emergence of a new hybrid species.The team says that the analysis reveals that polar bear DNA has lost diversity as the population has decreased, drifted apart, and become genetically isolated, suggesting today's bears have less adaptability to environmental change, habitat loss, pollution, and diseases they now face.What does the author say about the future of polar bears?()A They will not survive due to the melting occurring in the polar regions today.B We cannot be sure whether they will survive.C They will certainly survive after patrolling the planet's icy regions for millions of years.D We can help them to ride out the global warming this time again.

Judy is quite obedient while her younger sister always ____ her father around her little finger.A. wrecksB. wrestlesC. wrapsD. writes

My schoolmates watched time crawl every afternoon, waiting an ___ for the three o'clock bell. (eternal)

I try not to be biased(有偏见的) but I had my doubts about hiring Stevie. His social worker assured me that he would be a good, reliable busboy. But I had never had a mentally handicapped employee. He was short, a little fat, with the smooth facial features and thick-tongued speech of Down’s Syndrome. I thought most of my customers would be uncomfortable around Stevie, so I closely watched him for the first few weeks. I shouldn’t have worried. After the first week, Stevie had my staff wrapped around his stubby little finger, and within a month my regular trucker customers had adopted him as their official truck stop mascot(吉祥物). After that, I really didn’t care what the rest of the customers thought of him. He was like a 21-year-old in blue jeans and Nikes, eager to laugh and eager to please, but fierce in his attention to his duties. Every salt and pepper shaker was exactly in its place, not a bread crumb or coffee spill was visible when Stevie got done with the table. Our only problem was persuading him to wait to clean a table until after the customers were finished. Over time, we learned that he lived with his mother, a widow who was disabled. Money was tight, and what I paid him was probably the difference between them being able to live together and Stevie being sent to a group home. That’s why the restaurant was a gloomy place that morning last August, the first morning in three years that Stevie missed work. He was at the Mayo Clinic in Rochester getting a heart surgery. His social worker said that people with Down’s Syndrome often had heart problems at an early age and there was a good chance he would come through the surgery in good shape and be back at work in a few months. A ripple of excitement ran through the staff later that morning when word came that he was out of surgery, in recovery, and doing fine. Frannie, my head waitress, did a little dance when she heard the good news. Belle Ringer, one of our regular trucker customers, stared at her and asked, “Okay, Frannie, what was that all about?” “We just got word that Stevie is out of surgery and going to be okay.” “I was wondering where he was. I had a new joke to tell him. What was the surgery about?” Frannie quickly told Belle Ringer and the other two drivers sitting at his booth about Stevie’s surgery, then sighed: “Yeah, I’m glad he is going to be OK,” she said. “But I don’t know how he and his Mom are going to handle all the bills. From what I hear, they’re barely getting by as it is.” Belle Ringer nodded thoughtfully, and Frannie hurried off to wait on the rest of her tables. After the morning rush, Frannie walked into my office. She had a couple of paper napkins in her hand. “What’s up?” I asked. “I cleared off that table where Belle Ringer and his friends were sitting after they left, and I found this. This was folded and tucked under a coffee cup.” She handed the napkin to me, and three 20 bills fell onto my desk when I opened it. On the outside, in big, bold letters, was printed “Something For Stevie”. That was three months ago. Today is New Year’s Day, the first day Stevie is supposed to be back to work. His social worker said he had been counting the days until the doctor said he could work. I arranged to have his mother bring him to work, met them in the parking lot and invited them both to celebrate his day back. I took him and his mother by their arms. “To celebrate you coming back, breakfast for you and your mother is on me.” I led them toward a large corner booth. I could feel and hear truck customers and the rest of the staff following behind as we marched through the dining room. We stopped in front of the big table. Its surface was covered with coffee cups and dinner plates, all sitting slightly on dozens of folded paper napkins. “First thing you have to do, Stevie, is clean up this mess,” I said. Stevie looked at me, and then pulled out one of the napkins. It had “Something for Stevie” printed on the outside. As he picked it up, two 10 bills fell onto the table. Stevie stared at the money, then at all the napkins peeking from beneath the tableware, each with his name printed on it. I turned to his mother. “There’s more than 10,000 incash and checks on that table, all from truckers and trucking companies that heard about your problems. Happy Thanksgiving!” While everybody else was busy shaking hands and hugging each other, Stevie, with a big, big smile on his face, was busy clearing all the cups and dishes from the table. 【小题】(1) Why did the author have doubts about hiring Stevie?A.Stevie was not that reliable.B.Stevie was mentally disabled.C.Stevie was too short and fat.D.Stevie was bad-tempered.【小题】(2) What made the author not fully satisfied with Stevie’s work?A.That he made customers uncomfortable.B.That he couldn’t pay attention to his duties.C.That he often spilled cups of coffee.D.That he usually cleaned the table too early.【小题】(3) By saying the underlined words in Paragraph 3, the author meant that the money she paid Stevie ___.A.could help Stevie out of the troubleB.could send Stevie to a group homeC.couldn’t thoroughly solve Stevie’s problemD.could make little difference to Stevie’s life【小题】(4) Why did the author ask Stevie to clean up the mess on the table?A.Stevie could pick up the money that was given to him.B.The table was so dirty that it needed cleaning.C.It was Stevie’s duty to clean the table.D.She wanted to congratulate Stevie on his coming back.【小题】(5) What made Stevie popular among the staff and customers in the restaurant?A.His special appearance.B.His hard work and optimism.C.His funny speeches and actions.D.His kind-hearted behaviour..

The snake can stay in a tree without moving for ____ a bird may mistake it for a branch.A. quite longB. long enoughC. so longD. very long

introvert cling to go hand in hand with be aware of declaration1. Three months after a powerful tsunami(海啸), his parents still ________ the hope that he was still alive.2. Most students ________ the importance of learning English because English increases the chance of getting a good job.3. Envy is considered one of the seven deadly sins(罪), and it tend to ________ destructive criticism towards the object of envy.4.It is assumed that ________ people are going to be more effective leaders in complex and unpredictable settings.5. The new President announced that any kind of sanctions(制裁) against his country would be taken as a ________ of war.

The fifth generation computers, with artificial intelligence, ________ and perfected now.A. developedB. have developedC. are being developedD. will have been developed

分录题（共1题，10.0分）1. (10.0分) Complete each phrase only with one word for each blank according to the Chinese expression given.do____ (进展好，情况不错)____ over (变成主要的，取而代之)all the____ (一直)____ time (久而久之；随着时间的推移)out of____ (出于同情)____ one's way (发现到某处的途径)take____ (照管)stay____ (留在原处不动)in____ (跟随)be____ with (关心，感兴趣)