阅读理解

    American Sign Language, often called ASL, is used by most people with hearing problems in the United States and Canada.

    Besides ASL, there are more than fifty sign languages used throughout the world today, including Mayan Sign, British Sign, Israeli Sign, and Chinese Sign. Like spoken languages, sign languages are different from each other. But all sign languages are based on sight instead of sounds.

    Sign languages have several main visual (视觉) parts that work together to express meaning. The first part is the shape made by the hands. Movement is also important. Moving the body or organs (器官) like hands affects the meaning of the shape. The place where the sign is made and the direction the hands face are crucial as well. Other visual clues (线索), such as the expression on a person's face, can sometimes change a sign's meaning. For example, a change in a smile can show whether a signer is happy, very happy, or overjoyed. Raising the eyebrows can mark a question.

    In sign languages, the visual parts are combined (结合) in different ways to create signs.

These signs stand for things, actions, feelings, and ideas. ASL has about 4,000 different signs. Like spoken  languages,  sign  languages  cannot  be  translated  word-for-word.  

    For English word may be represented by a series of signs in ASL. Or several English words may be

represented by a single ASL sign. Unlike spoken languages, the signs are organized according to sign-language grammar and the most important word or idea is signed first.

    In ASL, the letter signs are made with one hand. Signers would rarely, if ever, spell out all the words they are signing. That would be as awkward and slow as speakers spelling each spoken word. However, American Sign Language does not have signs for proper names, so signers may use the alphabet to spell these. Also, sign languages often borrow words from other languages. They may spell words using finger spelling which is done with a set of hand shapes that stand for letters of the alphabet.

    Sign languages  develop  naturally  when  people  with  shared  culture  and  needs  want  to communicate with each other. Signers are closely linked to each other, perhaps more than to speaking people in their own communities. Signers share points of view, values, needs, and problems,as well as languages.

    In 1826, a Frenchman named Niepce needed pictures for his business .But he was not a good artist .So he invented a very simple camera. He put it in a window of his house and took a picture of his garden .That was the first photo.

    The next important date in the history of photography was in 1837. That year, Daguerre, another Frenchman, took a picture of his reading room .He used a new kind of camera in a different way. In his picture you could see everything very clearly, even the smallest thing. This kind of photo was called a Daguerreotype.

    Soon, other people began to use Daguerre's way. Travelers brought back wonderful photos from all around the world .people took picture of famous buildings, cities and mountains.

    In about 1840, photography was improved .Then photographers could take pictures of people and moving things .That was not simple .The photographers had to carry a lot of films and other machines. But this did not stop them, for example, some in the United States worked so hard. Mathew Brady was a famous American photographer. He took many pictures of great people .The pictures were unusual because they were very lifelike.

    Photographers also became one kind of art by the end of the 19th century. Some photos were not just copies of the real world .They showed feelings like other kinds of art.

     Kumar and his two friends built a robot and named it Athena. They would go for Battle of the Bots--the city's biggest robot competition, and it would start in two days. The winning team would get $5,000.

     "How are we going to beat (打败) the Cougars?" asked Alex. The Cougars was the team that won the last two years' competitions.

    Kumar said, "The Cougars always build a big and strong (强壮的) robot. But usually their robot isn't very fast."

    "Our robot is fast," Alyssa said.

    "Yes!" Kumar said. "Don't worry. I have a plan for how to do it." Kumar told the group his plan and they began to work.

    Two days later, the competition began. Kumar said to his friends, "I' m sure the plan will work and Athena will win. Just wait and see."

    Athena won all of her first battles (较量). The Cougars' big, strong robot, The Avenger, did well, too. By the end of the day, The Avenger and Athena were the only two robots left in the competition.

    Soon the battle between Athena and the Avenger began. The Avenger lunged (猛扑) for Athena, but the small robot was too quick for him. Athena went behind The Avenger and, before the larger robot had time to turn, Athena hit (攻击) him from behind. The Avenger fell" down and couldn't move.

    The three friends all jumped up excitedly. "Now it's time for the real question," said Alex“      ”

C

    Google and Toyota have worked together to create a new smart car. It can run on the road without a driver. It drives itself. The self-driving car hasn't been on sale to the public, so we don't know how much it costs. Another thing most people want to know is whether it will be safe enough to run on the road.

The self-driving car uses electricity (电) as its power, and it can't drive very quickly—the top speed would be 25 miles per hour. It is actually controlled by a computer system on the car. The system keeps on collecting information by some video cameras inside the car and a LIDAR sensor(激光达传器) on top of it. A computer processes the information and decides what to do. "The self'-driving car has only buttons (按钮) for go and stop, so it's very easy to use," an engineer of Google says. "And what's more, it will make car accidents fewer and make the world a safer place." The self-driving car has driven hundreds of thousands of miles in California, and it has only gotten into two accidents by human mistake.

    According to CNN, self-driving cars will also help to reduce the number of cars in big cities. "Self'-driving cars would be able to send you to the workplace and then pick up another person instead of stopping in a parking lot."

    In some science fiction(科幻)movies, people in the future have their own robots.These robots are like humans (人类). They help with the housework and do difficult and heavy jobs.

    So me scientists think that there will be such robots in the future. But they say it may take hundreds of years. Scientists are now trying to make robots look like people and do the same things as us. Japanese companies have already made robots walk and dance.

    James White thinks that it will be difficult for a robot to do the same things as a person. But other scientists don't think so. They think robots can do the same thing as us in 50 years.

    Robot scientists are trying to make robots look like not only people but also animals. For example, there are already robots working in factories. They do easy jobs over and over again. People would not like to do such jobs and would get bored(感到无聊的). But robots will never get bored and tired.

    In the future, there will be more robots everywhere, and humans will have less work to do. New robots will have many different shapes(形状). Some will look like humans, some will look like dogs, some will look like hands, and others may look like snakes. After an earthquake(地震), a snake robot could help look for people under buildings. We never know what will happen in the future!

    As space science develops, man has learned more and more about space. Space is not only amazing but also dangerous. While working in space, spacemen are facing danger as well as success.

    Scientists have found out that the radiation(辐射) is the greatest danger to spacemen in space. When spacemen are working in space, they are in danger of the radiation from the sun and other stars, which is bad for their health. The harm of the radiation won't be found until their children even grandchildren are born. Some special medicine may work a little, but no really effective medicine has been found so far. Space rubbish is also thought to be a great danger to spacemen. It's reported that there were 9,000 man-made things flying in space. About 30% of these are satellites, 10% are spaceships, and the rest are space rubbish. An explosion(爆炸) in space in 1999 made a cloud of 300,000fragments, each at least 4mm in size. A small piece of these even knocked a spaceship window and caused some damage(损坏).

    Scientists are watching and reporting any possible danger all the time. They are working to deal with space rubbish. Although space is really dangerous, it interests many people on the earth. In the near future, it may become possible for people to spend a few days in a space hotel. People may even choose to leave the earth and live in space in a few years. So scientists are doing everything they can to help improve the space environment.