Secret codes (密码) keep messages private. Banks, companies, and government agencies use secret codes in doing business, especially when information is sent by computer.
People have used secret codes for thousands of years.
There are three main types of cryptography.
A code uses symbols to replace words, phrases, or sentences. To read the message of a real code, you must have a code book.
| A．It is very hard to break a code without the code book. |
| B．In any language, some letters are used more than others. |
| C．Only people who know the keyword can read the message. |
| D．As long as there have been codes, people have tried to break them. |
| E．You can hide a message by having the first letters of each word spell it out. |
| F．With a code book, you might write down words that would stand for other words. |
| G．Another way to hide a message is to use symbols to stand for specific letters of the alphabet. |
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【推荐1】Why do we dream? It’s a question researchers have been studying for years. Now new research suggests that some dreams may result from the brain’s effort to keep learning, even as we sleep.
In a study in Boston,100 volunteers were trained for an hour on a maze(迷宫). They tried to find their way through the difficult puzzle as quickly as possible. Then half of the volunteers were allowed to sleep for 90 minutes. The other half stayed awake, reading or relaxing. The ones who slept were asked to describe their dreams when they woke up.
After the rest, the volunteers were asked again to solve the maze. Those who hadn’t slept showed no improvement or did even worse after the break. Sleepers who didn’t report any mazerelated dreams did better but showed only a little improvement. However, four naptakers who reported dreaming about the maze showed a surprising improvement. They scored 10 times higher after sleeping and dreaming about the maze.
Even though the number of dreamers was small, the researchers noted that the gap in learning between the dreamers and nondreamers was so wide that the finding was significant(有意义的).
The dreamers had all performed poorly on the test before dreaming about it. That suggests that struggling with a task might be the trigger that leads the sleeping brain to focus on it and work on how to deal with it.
“It’s almost as if your brain is going through everything that happened today,” Dr Stickgold, a scientist at Harvard Medical School, said. ”The things you’re obsessed(迷住) with are the ones that your brain forces you to continue to do with. ”
1. What were the volunteers asked to do after the rest?| A．To work on a new maze. |
| B．To continue to do the maze. |
| C．To talk with each other about their dreams. |
| D．To tell what they thought about the maze. |
| A．Those who didn’t sleep. |
| B．Those who slept but didn’t dream. |
| C．Those who dreamed about the maze while sleeping. |
| D．Those who thought about the maze before falling asleep. |
| A．chance | B．cause |
| C．way | D．idea |
| A．Learning While You Dream |
| B．What Dreams Stand for |
| C．Dream a Good Dream |
| D．Dreams and Health |
Empathy is our inherent ability to understand or feel what another person is experiencing from within the other person' s frame of reference. It allows us to connect with others who seem different, making us more aware of the things we have in comm on. When we tune in to empathize with others, we are more likely to act with sympathy to help reduce their suffering. And, when we increase our caring for the environment, we are more likely to make choices that help preserve it for future generations.
Although empathy is a vital element of our nature, research suggests that empathy can be taught, and that con tact with people who are different from us in a safe, empathic way is the first step toward reducing prejudice. This is where museums have a role to play. Museums are safe and informal learning platforms, uniquely equipped to encourage visitors to imagine, explore, and experience rich human heritage and the natural world firsthand. They have the capability to bring together arts, techno logy, sciences, and literature to show how all living things are linked to each other.
Museums inspire empathy in us in a number of ways. Through their social and educational mission (使命), museums can provide a safe space for experiencing our collective behavior, knowledge, complex histories, and values. By putting people in closeness to other people’s experiences, their cultures and stories, museums can help us awaken to different realities and multiple perspectives(视角) that exist around us. Personal and diverse encounters (意外的相遇) with people from other cultures -and their ideas, stories, and artifacts -create opportunities for authentic dialogue with “the other”: someone who is different from us, but shares our world. Also, museums often present the stories of people and places far away. Telling stories from the point of view of the people and cultures featured can also increase our sense of shared humanity, as we see how others face fears, biases, and challenges similar to our own. More importantly, museums encourage contemplation(沉思) of our world by providing a space where we can slow down and be with what is before us. Unlike many everyday settings where the goal is clear, people explore in museums on their own schedule, moving from exhibit to exhibit as they see fit, following their own internal guidelines. This naturally allows for a more reflective experience. Through this reflection, visitors can acquire a deeper understanding of the viewpoints of others and recognize their own connection to all of humanity and the planet.
Museums and empathy | |
| Concept of empathy and | Empathy refers to the ability to place oneself in another's It can make one |
| Museums Museums show how all living things are | |
| How museums increase empathy | Museums hold a mirror to society, through which visitors get As a place of storytelling museums can help people breakdown prejudice and increase their sense of shared humanity. Museums provide a safe space where visitors can take time to |
【推荐3】It’s never easy to explain exactly when a specific language began, and in the case of English we can hardly regard it as a separate language before the Anglo-Saxons came to Britain. Germanic invaders (入侵者) came and settled in Britain from the north-western coastline of continental Europe in the fifth centuries. The invaders all spoke a language that was Germanic (related to Dutch, Frisian, German and the Scandinavian languages), but we’ll probably never know how different their speech was from that of their continental neighbors.
The reason that we know so little about the language in this period is that we do not have much in the way of written records from any of the Germanic languages until several centuries later. When Old English writings began to appear in the seventh and eighth centuries there was a good deal of regional variation (变化), but not more than that found in later periods.
The Celts already lived in Britain when the Anglo-Saxons arrived, but there are few obvious signs of their language in English today. Some scholars have suggested that the Celtic tongue might have had some influence on the grammatical development of English, particularly in some parts of the country, but this is highly speculative (猜测). The number of borrowed words that have entered Old English from this language is very small. Those that survive in modern English include “comb” (a type of valley), alongside some place names.
1. When did the English language begin?| A．After the Anglo-Saxons came to Britain. |
| B．Before the Germanic invaders settled in Britain. |
| C．At a time that no one will know for certain. |
| D．At the same time as Germanic languages began. |
| A．Great Britain | B．Africa |
| C．Europe | D．Ireland |
| A．There are no written records from the Germanic languages. |
| B．Old English didn’t have any written system. |
| C．Much of the written records have been lost. |
| D．There was a good deal of variation in the records. |
| A．It influenced the grammatical development of English. |
| B．It had little influence on modern English. |
| C．It borrowed a few words from Old English. |
| D．It greatly enriched modern English vocabulary. |
【推荐1】Do you edit text messages carefully before sending them? If so, you may be the kind of person who takes pride in crafting even the simplest message.
A new book Writing For Busy Readers makes the argument for being the careful kind of writer, even in informal messages. It lays out the data for sharp, simple writing.
Todd Rogers and Jessica Lasky-Fink are behavioural scientists, both at Harvard. Their “Writing For Busy Readers” is cleverly titled: all readers are busy nowadays. People are filled constantly with messages, from the mailbox to the inbox to the text-message reminder. What to read, what to skim and what to ignore are decisions that nearly everyone has to make dozens, or even hundreds of times a day.
The authors present well-established principles that have long been prized in guide s to writing including The Economist’s style book: cut unnecessary words, choose words everyone knows and keep sentences simple.
Take “less is more”. Most books on writing well suggest cutting off needless words. However, in Writing for Busy People, the authors have tested the principles. For example, in an email to thousands of school-board members asking them to take a survey, cutting the length from 127 to 49 words almost doubled the response rate (from 2.7% to 4.8%).
The researchers found that a longer message makes recipients (收件人) think the task (such as filling out a survey) will take longer, too. Writers must sometimes choose to be informal but effective instead of sympathetic but ignored. From Facebook posts to online-travel reviews, even brief, informal pieces of writing that follow these rules get more likes, shares and so on. From essays to text messages organizing dinner plans, devoting time to the needs of readers has evident benefits. If you are so busy that you write a badly-organized message that readers scan, ignore and delete, then you might as well have not written it at all.
1. What is the purpose of the question in Paragraph 1?| A．To raise people’s interest in simple writing. | B．To correct the old view about text messages. |
| C．To reveal the negative effects of messages. | D．To improve the texting skills of people. |
| A．It emphasizes the importance of timely messages. |
| B．It brings evidence on the well-established principles. |
| C．It was written by a well-known author Todd Rogers. |
| D．It was once published in the magazine The Economist. |
| A．Brief writing gains few popularity. | B．Messages are too short to understand. |
| C．People tend to overlook long messages. | D．Sympathetic messages get many responses. |
| A．How to write effectively. | B．When to text messages. |
| C．The languages used in writing. | D．The methods of sending emails. |
【推荐2】Scientists at the University of Oxford have developed new artificial intelligence (AI) software to recognize and follow up the faces of individual chimpanzees (黑猩猩) in the wild. The new software will allow researcher and wildlife conservationists to greatly cut back on time spent analyzing videos, according to the new paper published today in Science Advances.
“For species like chimpanzees, which have complex social lives and live for many years, getting photos of their behavior from short-term field research can only tell us so much.” says Dan Sehofield, researcher and DPhil student at Oxford University’s Primate Models Lab, School of Anthropology. “By taking advantage of the power of machine learning to unlock large video files, it makes it possible to measure behavior over the long term.”
The computers model was trained using over 10 million images (影像) from Kyoto University’s Primate Research Institute (PRI) video files of wild chimpanzees in Guinea, West Africa. The new software is the first to continuously track and recognize individuals in a wide range of posed, performing with high accuracy in difficult conditions such as low lighting and poor image quality.
“Access to this large video file has allowed us to use the newest deep neural networks to train models at a scale that was previously not possible,” says Arsha Nagrani, co-author of the study and DPhil student at the Department of Engineering Science, University of Oxford. “Additionally, our new software differs from previous primate face recognition software in that it can be applied to raw videos with limited manual intervention (人工干预) or pre-processing, saving hours of time.”
The technology has potential for many uses, such as monitoring species for conservation. Although the present application focused on chimpanzees, the software provided could be applied to other species, and help drive the adoption of AI systems to solve a range of problems in the wildlife sciences.
1. What’s the purpose of developing the new software?| A．To save wildlife researchers’ time spent in the wild. |
| B．To keep track of wildlife conservationists’ behavior. |
| C．To protect chimpanzees and help them to live longer. |
| D．To recognize and track the faces of wild chimpanzees. |
| A．Getting photos. | B．Analyzing videos. |
| C．The new AI software. | D．A powerful machine. |
| A．The unique advantages of the new software. |
| B．Some limitations of using the new software. |
| C．The working principles of the new software. |
| D．Controversial attitudes to the new software. |
| A．The new software has a quite bright future. |
| B．The application of the technology can be tough. |
| C．Technology is the final goal of scientific research. |
| D．AI systems are widely used in the wildlife sciences. |
【推荐3】Ah, Paris the incomparable ! Whether you've suddenly found yourself with travel brochures in your hand or you prefer to travel from your armchair, Paris is one of those cities with wide open arms. Where to begin? Well, follow me!
Louvre
Many people lose interest when you talk about museums, but you know where we are heading, don't you? This is one of the top 10. Wear comfortable shoes, prepare enough water, and know what you want to see. The Mona Lisa may not be your cup of tea, but we recommend at least Liberty Leading the People, The Raft of the Medusa, and so on.
Musée d’Orsaya
If you can do without art-although we doubt anyone can—we'd recommend that you walk inside this museum. The light inside is worth your attention. Once a train station, the Musée d’Orsay has been repurposed and is now a pleasing wonder with Postimpressionist paintings and more to suit most tastes.
The Seine River
All you have to do is decide which bank you prefer, left or right. Each has its unique pleasures. Home to cultural, fashion and artistic riches, the left bank is lined with cafés, which are a good place to meet your hero or heroine. But also consider the right bank, especially the Picasso Museum, an excellent place to hang around.
Giverny
Lying about 45 miles from Paris, this village is the hometown of the late artist Claude Monet. It is as if you've stepped into one of his paintings—a perfect blue-green bridge with water lilies (睡莲) fully open below and a warm peach-pink brick house. The whole scene is designed to please the eye.
1. What can visitors do in the Louvre?| A．Ride on a train. | B．Drink a cup of tea. |
| C．Appreciate Mona Lisa. | D．See Picasso paintings. |
| A．Louvre. | B．Musée d'Orsaya. | C．The Seine River. | D．Giverny. |
| A．They are suitable for art lovers. |
| B．They are all famous museums. |
| C．They are in the center of Paris. |
| D．They are the most popular places. |
