Knots are the kind of stuff that even myths are made of.In the Greek legend of the Gordian knot, for example, Alexander the Great used his sword to slice through a knot that had failed all previous attempts to unite it. Knots, enjoy a long history of tales and fanciful names such as “Englishman’s tie, ” “and “cat’s paw. ” Knots became the subject of serious scientific investigation when in the 1860s the English physicist William Thomson (known today as Lord Kelvin) proposed that atoms were in fact knotted tubes of ether（醚）. In order to be able to develop the equivalent of a periodic table of the elements, Thomson had to be able to classify knots — find out which different knots were possible. This sparked a great interest in the mathematical theory of knots.
A mathematical knot looks very much like a familiar knot in a string, only with the string’s ends joined. In Thomson’s theory, knots could, in principle at least, model atoms of increasing complexity, such as the hydrogen, carbon, and oxygen atoms, respectively. For knots to be truly useful in a mathematical theory, however, mathematicians searched for some precise way of proving that what appeared to be different knots were really different — the couldn’t be transformed one into the other by some simple manipulation（操作）. Towards the end of the nineteenth century, the Scottish mathematician Peter Guthrie Tait and the University of Nebraska professor Charles Newton Little published complete tables of knots with up to ten crossings. Unfortunately, by the time that this heroic effort was completed, Kelvin’s theory had already been totally discarded as a model for atomic structure. Nevertheless, even without any other application in sight, the mathematical interest in knot theory continued at that point for its own sake. In fact, mathematical became even more fascinated by knots. The only difference was that, as the British mathematician Sir Michael Atiyah has put it, “the study of knots became a special branch of pure mathematics. ”
Two major breakthroughs in knot theory occurred in 1928 and in 1984. In 1928, the American mathematician James Waddell Alexander discovered an algebraic expression that uses the arrangement of crossings to label the knot. For example, t2-t+1 or t2-3t+1, or else. Decades of work in the theory of knots finally produced the second breakthrough in 1984. The New Zealander-American mathematician Vaughan Jones noticed an unexpected relation between knots and another abstract branch of mathematics, which led to the discovery of a more sensitive invariant known as the Jones polynomial.What is surprising about knots?
| A．They originated from ancient Greek legend. |
| B．The study of knots is a branch of mathematics. |
| C．Knots led to the discovery of atom structure. |
| D．Alexander the Great made knots well known. |
What does the underlined word “that” in Paragraph 3 refer to?
| A．No other application found except tables of knots. |
| B．The study of knots meeting a seemingly dead end. |
| C．Few scientist showing interest in knots. |
| D．The publication of complete tables of knots. |
According to the passage, ______ shows the most updated study about knots.
| A．t2-t+1 | B．t2-3t+1 |
| C．Alexander polynomial | D．Jones polynomial |
Which one would be the best title for this passage?
| A．Mathematicians VS Physicians |
| B．To be or Knot to be |
| C．Knot or Atom |
| D．Knot VS Mathematics |
Suppose you want to bring home a new cat and are looking for a way to really make it feel at home. Actually, all you need to do is buy some nice cat furniture and have it in place by the time you bring it into your home.
The first thing that you should prepare is a cat house. Two to three feet off the ground is the best height. If you don’t have enough room for a cat house, a cat bed is also a nice choice.
Once you have a nice spot where your cat can go to feel safe, then it’s time to get cat furniture that offers your pet a nice place to play. One nice choice is cat trees. Scratching posts (猫抓板) are another great idea if you are short in space, but still want to give your cat a nice place where it can claw (抓) at instead of your own furniture.
If you’re looking for a great way to shop for cat furniture, simply turn on your computer and do some online shopping. In no time will you be able to skim all the offerings from many online stores. What’s great is that you can easily compare products and their prices, so you can get what you want at the best possible price. And, probably the nicest thing about online shopping is that your purchases may be shipped right to you, so you don’t have to waste time making a trip to the store.
So, if you have brought a new cat into your home, make sure that home is an inviting one by buying some new cat furniture. Without it, your cat might feel lost and unsafe, which you definitely do not want to happen.What should you do first before you bring a cat home?
| A．Find a proper place for the cat to sleep. |
| B．Buy a cat house and some cat furniture. |
| C．Learn how to take care of the cat. |
| D．Know how to buy cat furniture online. |
According to the author, the first concern for a cat house is __________.
| A．its height | B．its size | C．its price | D．safety |
What is the best choice for your cat to play with if you have little room?
| A．The cat bed. | B．Scratching posts. |
| C．Your own furniture. | D．Cat trees. |
What is the author’s advice on shopping for cat furniture?
| A．Compare products and their prices and get the cheapest ones. |
| B．Try to save time and money when you buy cat furniture. |
| C．Do some online shopping and get products with reasonable prices. |
| D．Buy furniture that can be shipped to you as quickly as possible. |
It was a Sunday morning, and I was in a terrible mood. Two of my friends had gone to the movies the night before and hadn’t invited me. I was in my room thinking of ways to make them sorry when my father came in. “Want to go for a ride, today, Beck? It’s a beautiful day.”
“No! Leave me alone!” Those were the last words I said to him that morning.
My friends called and invited me to go to the mall with them a few hours later. I forgot to be mad at them and went with them. I came home to find a note on the table. My mother put it where I would be sure to see it. “Dad has had an accident. Please meet us at Highland Park Hospital”.
When I reached the hospital, my mother came out and told me my father’s injuries were extensive. “Your father told the driver to leave him alone and just call 911, thank God! If he had moved Daddy, there’s no telling what might have happened. A broken rib(肋骨) might have pierced(穿透) a lung....”
My mother may have said more, but I didn’t hear. I didn’t hear anything except those terrible words: Leave me alone. My dad said them to save himself from being hurt more. How much had I hurt him when I hurled those words at him earlier in the day?
It was several days later that he was finally able to have a conversation. I held his hand gently, afraid of hurting him.
“Daddy... I am so sorry....”
“It’s okay, sweetheart. I’ll be okay.”
“No,” I said, “I mean about what I said to you that day. You know, that morning?”
My father could no more tell a lie than he could fly. He looked at me and said, “Sweetheart, I don’t remember anything about that day, not before, during or after the accident. I remember kissing you goodnight the night before, though.” He managed a weak smile.
My English teacher once told me that words have immeasurable power. They can hurt or they can heal. And we all have the power to choose our words. I intend to do that very carefully from now on.The author was in bad mood that morning because _______.
| A．his father had a terrible accident |
| B．he couldn’t drive to the mall with his friends |
| C．his friends hadn’t invited him to the cinema |
| D．his father didn’t allow him to go out with his friends |
Why did the author say sorry to his father in the hospital?
| A．Because he didn’t go along with his father. |
| B．Because he was rude to his father that morning. |
| C．Because he failed to come earlier after the accident. |
| D．Because he couldn’t look after his father in the hospital. |
The reason why the author’s father said he forgot everything about that day is that _______.
| A．he had a poor memory |
| B．he didn’t want to forgive his son |
| C．he just wanted to comfort his son |
| D．he lost his memory after the accident |
What lesson did Beck learn from the matter?
| A．Don’t treat your parents badly. |
| B．Don’t hurt others with rude words. |
| C．Don’t move the injured in an accident. |
| D．Don’t be angry with friends at small things. |
Eight-year-old Jesse Arbogast was playing in the sea late one evening in July when a 7-foot bull shark attacked him and tore off his arm. Jesse’s uncle jumped into the sea and dragged the boy to shore. The boy was not breathing. His aunt gave him mouth-to-mouth resuscitation(人工呼吸) while his uncle rang the emergency services. Pretty soon, a helicopter arrived and flew the boy to hospital. It was a much quicker journey than the journey by road.
Jesse’s uncle, Vance Folsenzier, ran back into the sea and found the shark that had attacked his nephew. He picked the shark up and threw it onto the beach. A coastguard shot the fish four times and although this did not kill it, the shark’s jaws relaxed so that they could open them, and reach down into its stomach, and pull out the boys’ arm.
At the Baptist Hospital in Pensacola, Dr Ian Rogers spent eleven hours reattaching Jesse’s arm. “It was a complicated operation,” he said, “but we were lucky. If the arm hadn’t been recovered in time, we wouldn’t have been able to do the operation at all. What I mean is that if they hadn’t found the shark, we wouldn’t have had a chance.”
According to the local park ranger Jack Tomosvic, shark attacks are not that common. “Jesse was just unlucky,” he says, “evening is the shark’s feeding time. And Jesse was in an area without lifeguards. This would never have happened if he had been in an area where swimming is allowed.”
When reporters asked Jesse’s uncle how he had had the courage to fight against a shark, he replied, “I was mad and you do some strange things when you’re mad.” What was the boy doing when the accident happened?
| A．Feeding a hungry shark. |
| B．Jumping into the rough sea. |
| C．Dragging a boy to the shore. |
| D．Swimming in a dangerous area. |
In which way did the boy’s uncle help with the operation?
| A．By finding his lost arm. |
| B．By making a phone call. |
| C．By flying him to hospital. |
| D．By blowing into his mouth. |
How was his uncle in time of danger?
| A．Careful. | B．Brave. | C．Optimistic. | D．Patient. |
According to Jack Tomosvic, _______.
| A．people are often attacked by sharks |
| B．sharks never attack people |
| C．Jesse was unlucky to have been attacked by a shark |
| D．Jesse was swimming in a safe area at the moment |
Deep in the Amazon forest, thousands of people still live in isolation from the rest of the world.
In a recent press release, the Brazilian government confirmed the existence of another isolated tribe of about 200 people living in the Vale do Javari reservation. The 200 people living in the Vale do Javari reservation. The reservation, located near the Peruvian border, is about the size of Portugal. At least another 14 isolated tribes, with a total population of about 2000, call the area home.
The newly observed group lives on four large straw-roofed buildings and grows corn, peanut and other crops.
Brazil’s National Indian Foundation (BNTF) first noticed the reservation in the forest using satellite maps, but it wasn’t until April that an airplane expedition was able to confirm the tribe’s existence. “The work of finding and protecting isolated groups is part of Brazilian public policy,” said the BNIF officer for Vale do Javari, Fabricio Amorim. “To confirm something like this takes years of hard work.”
BNIF estimates there are 68 isolated tribes living in the Amazon. The organization uses airplanes to avoid disturbing the tribes through personal contact, but that doesn’t mean others are so respectful of their right to privacy.
Illegal fishing, woodcutting and hunting bring people into the protected area. Oil exploration on the Peruvian side of the border is another threat. All kinds of criminals also invade the lands of the local groups, said Amorim. The outsiders can damage the land and influence the cultures of indigenous(土著的)peoples. They can also bring diseases which can wipe out the whole population that still lack even basic antibiotics(抗生素).
Brazil’s indigenous peoples won the legal right to their traditional lands in Brazil’s 1988 Constitution, which stated that all indigenous lands shall be divided and turned over to tribes within five years. Indigenous groups now control 11 percent of Brazil’s territory, including 22 percent of the Amazon.
Allowing indigenous groups the right homelands is not just a matter of human rights. The rest of the world can benefit from their knowledge. Mark Plotkin has spent years living with the people of the Amazon and learning from their traditional healers. In his lecture, he pointed out that many useful materials and knowledge, including numerous drugs, can be gained from listening to the indigenous groups of the Amazon. Besides this, they are also more effective at protecting the land, and less expensive, than hired rangers(护林人).The underlined word in the first paragraph probably means “a state of ”.
| A．separation | B．interaction |
| C．satisfaction | D．excitement |
From the passage we can learn that the tribes in the Amazon forest .
| A．only live on a reservation designated for them |
| B．prefer straw-roofed buildings to wooden ones |
| C．keep contact with the outside world through airplanes |
| D．have the legal right to the land they live on |
Which of the following is TRUE according to Amorim?
| A．Privacy violation is common among the Amazon tribes. |
| B．The laws dividing the lands of the tribes are far from enough. |
| C．Modern civilization endangers the tribes and their cultures. |
| D．It is hard to make public policy to protect primitive tribes. |
The last paragraph is mainly about .
| A．the lost human rights of the indigenous peoples |
| B．the benefits of protecting the primitive tribes |
| C．the value of traditional healing |
| D．the indigenous peoples as guardians of the Amazon forest |
The novelist, Harriet Beecher Stowe, born 200 years ago, was a poor housewife with six children, and she suffered from various illnesses. Driven by the hatred of slavery, she found time to write Uncle Tom’s Cabin, which became the most influential novel in American history and caused great change, both at home and abroad.
Today, however, the book has a different reputation, owing to the popular image of its character, Uncle Tom, whose name has become a saying for a cowardly（懦弱的）black man who betrays his race.
But this view is wrong: the original Uncle Tom was physically and morally strong, an inspiration for black people and other oppressed（被压迫的）people worldwide. Indeed, that was why, in the mid-19th century, Southerners attacked Uncle Tom’s Cabin as a dangerously destructive book, while Northern reformers—especially black people—often praised it.
The book was influential overseas too. In Russia it inspired Vladimir Lenin, who recalled it as his favorite book in childhood. It was the first American novel to be translated and published in China, and it fueled anti-slavery movements in Cuba and Brazil.
The book’s progressive appeal was the character of Uncle Tom himself: a strong man who is notable because he does not betray his race; one reason he gives up escaping from his plantation（种植园）is that he doesn’t want to put his fellow slaves in danger. And he is finally killed because he refuses to tell his master where two runaway slaves are hiding.
Unfortunately, these themes were lost in many of the stage versions of Uncle Tom’s Cabin.
The play, seen by more people than those who read the book, remained popular up to the 1950s and still appears occasionally. But in the play, Stowe’s revolutionary themes were drowned.
But it doesn’t have to be that way; indeed; during the civil rights era it was those who most closely resembled Uncle Tom—Stowe’s Uncle Tom, not the embarrassed one of popular myth—that proved most effective in promoting progress. Both Stowe and Uncle Tom deserve our reconsideration and our respect.Harriet Beecher Stowe wrote Uncle Tom's Cabin because she .
| A．wanted to earn money to support her family |
| B．tried to set an example to her six children |
| C．hated slavery from the bottom of her heart |
| D．had similar life experiences to Uncle Tom |
Which of the following is TRUE about the influence of the book?
| A．It was the first American novel to be translated into Russian. |
| B．It was the most influential book for Vladimir Lenin in his life |
| C．It also gave rise to anti-slavery movements in faraway Africa. |
| D．It inspired black people and people who were suffering in the world. |
What can we learn about Uncle Tom in the book?
| A．he helps his fellow slaves to avoid getting into danger. |
| B．He is a black man who betrays his race. |
| C．He manages to escape from the plantation. |
| D．He kills himself instead of giving away the slaves. |
According to the passage, which of the following is NOT true?
| A．The themes of revolution and progress in the book were lost in the play |
| B．There are more people who have read the book, Uncle Tom’s Cabin, than those who have seen the stage version. |
| C．The play was very popular and it is still put on from time to time today. |
| D．It was Uncle Tom in the book that promoted the progress of mankind. |
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