A recent study of ancient and modern elephants has come up with the unexpected conclusion that the African elephant is divided into two distinct (不同的) species.
The discovery was made by researchers at York and Harvard Universities when they were examining the genetic relationship between the ancient woolly mammoth and mastodon to modern elephants—the Asian elephant,African forest elephant,and African savanna elephant.
Once they obtained DNA sequences (序列) from two fossils (化石)，mammoths and mastodons,the team compared them with DNA from modern elephants.They found to their amazement that modern forest and savanna elephants are as distinct from each other as Asian elephants and mammoths.
The scientists used detailed genetic analysis to prove that the African savanna elephant and the African forest elephant have been distinct species for several million years.The divergence of the two species took place around the time of the divergence of Asian elephants and woolly mammoths.This result amazed all the scientists.
There has long been debate in the scientific community that the two might be separate species,but this is the most convincing scientific evidence so far that they are indeed different species.
Previously,many naturalists believed that African savanna elephants and African forest elephants were two populations of the same species,despite the elephants’ significant size differences.The savanna elephant has an average shoulder height of 3.5 metres while the forest elephant has an average shoulder height of 2.5 metres.The savanna elephant weighs between six and seven tons,roughly double the weight of the forest elephant.But the fact that they look so different does not necessarily mean they are different species.However the proof lay in the analysis of the DNA.
Alfred Roca,assistant professor in the Department of Animal Sciences at the University of Illinois,said,“We now have to treat the forest and savanna elephants as two different units for conservation purposes.Since 1950,all African elephants have been conserved as one species.Now that we know the forest and savanna elephants are two very distinctive animals,the forest elephant should become a bigger priority(优先) for conservation purposes.”One of the fossils studied by the researchers is that of .
| A．the Asian elephant |
| B．the forest elephant |
| C．the savanna elephant |
| D．the mastodon elephant |
The underlined word “divergence” in Paragraph 4 means “ ”.
| A．evolution |
| B．exhibition |
| C．separation |
| D．examination |
The researchers’ conclusion was based on a study of the African elephant’s .
| A．DNA |
| B．height |
| C．weight |
| D．population |
What are Alfred Roca’s words mainly about?
| A．The conservation of African elephants. |
| B．The purpose of studying African elephants. |
| C．The way to divide African elephants into two units. |
| D．The reason for the distinction of African elephants. |
Which of the following can be the best title for the passage?
| A．Naturalists’ Beliefs about Elephants |
| B．Amazing Experiments about Elephants |
| C．An Unexpected Finding about Elephants |
| D．A Long Scientific Debate about Elephants |
If teens could reduce the salt they take in every day by 3,000 milligrams (mg), they would cut their risk of heart disease and stroke(中风) greatly in adulthood, researchers say.
Based on the results of a computer modeling analysis, researchers found that a 3,000 mg reduction in sodium(钠) by teenagers could reduce hypertension by 30 percent to 43 percent when they become adults.
Hypertension, or high blood pressure, is a common condition that may have no symptoms for years, but can eventually cause serious health conditions, including heart attack and stroke.
Other benefits over time as teens hit 50 years of age include a 7-12 percent reduction in coronary heart disease(冠心病), an 8-14 percent reduction in heart attacks, and a 5-8 percent reduction in stroke.
Fast food typically contains too much sodium. One bag of Nacho Cheese Doritos has 310 milligrams. Pizza is one of the biggest problems for teens when it comes to sodium, according to data from the National Center for Health Statistics.
“The additional benefit of lower salt intake early is that we can hopefully change the expectations of how food should taste, ideally to something slightly less salty,” says Dr. Kirsten Bibbins-Domingo, the lead author of the study and associate professor of medicine at the University of California, San Francisco.
“Most of the salt we eat is not from our salt shaker(盐瓶), but salt that is already added in food that we eat.” she added.Which is a benefit of a low sodium diet according to the text?
| A．No risk of heart disease. | B．Smaller chance of stroke. |
| C．Low blood pressure. | D．Slightly more heart attacks. |
According to the text, 3,000 mg less salt intake daily will reduce hypertension by ________ in adulthood.
| A．7%-12% | B．8%-14% | C．30%-43% | D．5%-8% |
What does Dr Kirsten Bibbins-Domingo mean in the last two paragraphs?
| A．A lower sodium diet can get teenagers used to less salty food. |
| B．A good eating habit can help teens have less junk food. |
| C．Teens should avoid pizzas and other salty foods. |
| D．We can add more salt from our salt shaker to the food. |
Which of the following can be the best title for the text?
| A．Teens Cutting Salt for Healthier Adulthood |
| B．Diet and Health |
| C．Sodium Brings Health Concerns |
| D．A Cause of Hypertension |
As the forceful king of Macedonia(马其顿), Alexander the Great overthrew the Persian Empire, becoming a hero that would survive centuries after his death.
Born in 356 B.C., Alexander III was the son of Philip II and Olympias. Alexander’s parents wanted him to receive the finest education, and arranged for him to study under Aristotle, regarded as one of the greatest scholars.
Alexander’s father was a strong leader. Philip II built an impressive army and established the Macedonian kingdom; he was even planning to attack Persia shortly before his death.
In 336, Philip was murdered by one of his guards. Although it was obvious that the guard had a personal hatred, there are clues that other people were related to it.
After Alexander was cleared as a suspect, he succeeded his father without opposition, and killed those said to be responsible for his father’s murder, as well as all rivals. He was then just 20 years old. He then prepared to attack Persia.
In the spring of 334, Alexander led the army made up of nearly 50,000 soldiers into Asia, which is called “the most powerful military expedition ever to leave Greece”, He soundly defeated the Persian army at the Granicus River, sending a strong message to Darius III, leader of the Persian Empire.
In 333, Alexander faced Darius at Issus, a mountain pass. The Macedonian army was greatly outnumbered but able to work the narrow mountain passageway to their advantage. Darius managed to escape. Continuing down the Mediterranean Coast, Alexander took every city in his path.
In 332 Alexander declared Egypt to be part of the Greek Empire and was crowned Pharaoh(法老).
When Alexander left Egypt in 331, he defeated the Persians again and was crowned leader of Asia.
In 323, however, Alexander developed a fever on the way back home and died 10 days later at Babylon. He was just 33 years old. What can we know about Philip’s death?
| A．He was killed by someone intending to take power from him. |
| B．Alexander sent someone who hated Philip to kill him. |
| C．His death was related to his plan of fighting Persia. |
| D．The murder might be organized by a group of people. |
The Macedonian army could defeat the Persians at Issus mainly because _________.
| A．Darius didn’t command his army in the battlefield |
| B．Macedonian soldiers were more than the Persian soldiers |
| C．Macedonian soldiers could fight better at the mountain pass |
| D．Macedonia was more powerful than the Persian Empire |
In which order did Alexander do the following things?
a．Totally overthrew the Persian Empire.
b．Defeated the Persian army at Issus.
c．Was crowned Pharaoh of Egypt.
d．Defeated the Persian army at the Granicus River.
e．Became the leader of Macedonia.
| A．e, d, b, c, a | B．d, e, a, c, b |
| C．e, b, d, c, a | D．d, a, c, e, b |
According to the passage, we can infer _________.
| A．Aristotle taught Alexander how to defeat other nations |
| B．Alexander was happy about his father’s death |
| C．Persia is tougher to defeat than Egypt |
| D．Macedonia soon declined after Alexander died |
It is six o’clock in the morning. You are asleep in my left arm and I am learning the art of one-handed typing. Your mother, more tired yet more happy than I’ve ever known her, is sound asleep in the room next door.
When you’re older we’ll tell you that you were born in Hong Kong in the lunar year of the pig. “It's a boy, so lucky,” our neighbours told us. They said you were the first baby to be born in the block this year. This, they told us, was good Feng Shui, in other words, a positive sign. Naturally your mother and I were only too happy to believe that.
Your coming has turned me upside down and inside out. I am pained by the memory of each suffering child I have come across on my journeys as a journalist. To tell you the truth, it’s nearly too much for me to even think of the children being hurt and abused and killed.
Last October, in Afghanistan, when you were growing inside your mother, I met Sharja, aged twelve, motherless, fatherless, guiding me through the grey ruins of her home. Everything was gone, she told me.
There is another memory of Rwanda, and the churchyard where I found a mother and her three young children huddled(蜷缩) together where they’d been beaten to death. The children had died holding on to their mother.
Daniel, these memories explain some of the protectiveness I feel for you, and the occasional moments of blind terror when I imagine anything bad happening to you. We can see that this text is written to ________.
| A．the author’s wife | B．the author’s neighbour |
| C．Daniel | D．a suffering child |
The author mentions some of his painful memories because ________.
| A．he wants his son to care for others |
| B．he feels more pain thinking about them as a father |
| C．he hopes to forget the tragedies he witnessed |
| D．his experience has affected his mental health |
The underlined word “blind” in the last paragraph means ________.
| A．unable to see | B．meaningful |
| C．not clear | D．not based on reason |
Which of the following words best describes the author’s feeling when typing this text?
| A．Relieved. | B．Regretful. | C．Loving. | D．Calm. |
Going to school means learning new skills and facts in different subjects. Teachers teach and students learn, and many scientists are interested in finding ways to improve both teaching and learning processes.
Sian Beilock and Susan Leving, two psychologists at the University of Chicago, are trying to learn about learning. In a new study about the way kids learn math in elementary school, Beilock 
and Levine found a surprising relationship between what female teachers think and what female students learn: If a female teacher is uncomfortable with her own math skills, then her female students are more likely to believe that boys are better than girls at math. “If these girls keep getting math-anxious female teachers in later grades, it may create a snowball 
effect on their math achievement,” Levine told Science News. The study suggests that if these girls grow up believing that boys are better at math than girls are, then these girls may not do as well as they would have if they were more confident.
Just as students find certain subjects to be difficult, teachers can find certain subjects to be difficult to learn—and teach. The subject of math can be particularly difficult for everyone.
The new study involved 65 girls, 52 boys and 17 first-and second-grade teachers in elementary schools in the Midwest. The students took math achievement tests at the beginning and end of the school year, and the researchers compared the scores.
The researchers also gave the students tests to tell whether the students believed a math superstar had to be a boy. Then the researchers turned to the teachers: To find out which teachers were anxious about math, the researchers asked the teachers how they felt at times when they came across math, such as when reading a sales receipt. A teacher who got nervous looking at the numbe
rs on a sales receipt, for example, was probably anxious about math.
Boys, on average, were unaffected by a teacher’s anxiety. On average, girls with math-anxious teachers scored lower on the end-of-the-year math tests than other girls in the study did. Plus, on the test showing whether someone thought a math superstar had to be a boy, 20 girls showed feeling that boys would be better at math—and all of these girls had been taught by female teachers with math anxiety.
According to surveys done before this one, c
ollege students who want to become elementary school teachers have the highest levels of anxiety about math. Plus, nine of every 10 elementary teachers are women, Levine said. Sian Beilock and Susan Levine carried out the new research in order to ___________.
| A．know the effects of teaching on learning | B．study students’ ways of learning math |
| C．prove women teachers are unfit to teach math | D．find better teaching methods for teachers |
The underlined
part in paragraph 2 most probably means that girls may ___________.
| A．end up learning math anxiety from their teachers | B．study the ways their female teachers behave |
| C．have an influence on their math-anxious female teachers | |
| D．gain unexpected achievement in such subjects as math |
In the study, what were the teachers required to do?
| A．Prepare two math achievement tests for the students | B．Tell their feelings about math problems |
| C．Answer whether a math superstar had to be a boy | D．Compare the students’ scores after the math tests |
What is the finding of the new study?
| A．No male students were affected by their teachers’ anxiety |
| B．Almost all the girls got lower scores in the tests than the boys |
| C．About 30% of the girls thought boys are better at math than girls |
| D．Girls with math-anxious teachers all failed in the math tests |
Which of the following is TRUE according to the text?
| A．117 students and teachers took part in the new study |
| B．The researchers felt surprised at the findings of their study |
| C．Beilock and Levine are interested in teaching math |
| D．Men teachers are better at teaching math than women teachers |
Today, there’s hardly an aspect of our life that isn’t being upended by the tons of information available on the hundreds of millions of sites crowding the Internet, not to mention its ability to keep us in constant touch with each other via electronic mail. “If the automobile and aerospace technology had exploded at the same pace as computer and information technology,” says Microsoft, “a new car would cost about $ 2 and go 600 miles on a small quantity of gas. And you could buy a Boeing 747 for the cost of a pizza.”
Probably the biggest payoff, however, is the billions of dollars the Internet is saving companies in producing goods and serving for the needs of their customers. Nothing like it has been seen since the beginning of the Industrial Revolution, when power-driven machines began producing more in a day than men could turn out in nearly a year. “We view the growth of the Internet and e-commerce as a global trend,” says Merrill Lynch, “along the lines of printing press, the telephone, the computer, and electricity.”
You would be hard pressed to name something that isn’t available on the Internet. Consider: books, health care, movie tickets, construction materials, baby clothes, stocks, cattle feed, music, electronics, antiques, tools, real estate, toys, autographs of famous people, wine and airline tickets. And even after you’ve moved on to your final resting place, there’s no reason those you love can’t keep in touch. A company called FinalThoughts.com offers a place for you to store “afterlife e-mails” you can send to Heaven with the help of a “guardian angel”.
Kids today are so computer literate that it in fact ensures the United States will remain the unchallenged leader in cyberspace for the foreseeable(能预测的) future. Nearly all children in families with incomes of more than $75,000 a year have home computers, according to a study by the David and Lucile Pa
ckard Foundation. Youngsters from ages 2 to 17 at all income levels have computers, with 52% of those connected to the Internet. Most kids use computers to play games (some for 30 hours or more a week), and many teenage girls think nothing of rushing home from school to have e-mail chats with friends they have just left.
What’s clear is that, whether we like it or not, the Internet is an
ever growing part of our lives and there is no turning back. “The Internet is just 20% invented,” says cyber pioneer Jake Winebaum. “The last 80% is happening now.”What can we learn from the Microsoft’s remark?
| A．Today’s cars and airplanes are extremely overpriced. |
B．Information technology i s developing at an amazing speed. |
| C．Information technology has reached the point where improvement is difficult. |
| D．There’s more competition in information technology industry than in car industry. |
According to the author, the biggest benefit of the Internet is that___.
| A．it saves companies huge amounts of money | B．it speeds up profit making |
| C．it brings people incredible convenience | D．it provides easy access to information |
The author gives the example of FinalThoughts.com to make the point that____.
| A．there are some genius ideas on the Internet | B．almost anything is available on the Internet |
| C．people can find good bargains on the Internet | D．some websites provide novel services to increase hits |
What can we learn from the fourth paragraph?
| A．There is a link between income and computer ownership. |
| B．Many American children don’t put computers to good use. |
| C．Studies show that boys are more computer literate than girls. |
| D．The U.S. will stay ahead in the information technology in years. |
Which sentence has the phrase that possesses the same meaning as the one underlined in the fifth paragraph?
| A．Some can tell you that he has changed their lives, while others think nothing of him. |
| B．Think nothing of it. It was my pleasure. |
| C．He thinks nothing of staying up all night in the Café bar. |
| D．He thinks nothing of the pain in his back for the moment. |
What is the message the author intends to convey?
| A．The Internet is going to get firm hold of our lives some day. |
| B．The Internet is going to influence our lives even more greatly. |
| C．We should have a positive attitude towards the changes the Internet brings. |
| D．Children should be well prepared for the challenges in the information age. |
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