Transparent animals let light pass through their bodies the same way light passes through a window. These animals typically live between 

the surface of the ocean and a depth of about 3,300 feet—as far as most light can reach. Most of them are extremely delicate and can be 

damaged by a simple touch. Sonke  Johnsen, a scientist in biology, says, “These animals live through their life alone. They never

touch anything unless they're eating it, or unless something is eating them.”

And they are as clear as glass. How does an animal become see-through? It's trickier than you might think.

      The objects around you are visible because they interact with light. Light typically travels in a straight line. But some materials slow and

 scatter(散射) light, bouncing it away from its original path. Others absorb light, stopping it dead in its tracks. Both scattering and absorption

 make an object look different from other objects around it, so you can see it easily.

But a transparent object doesn't absorb or scatter light, at least not very much, Light can pass through it without bending or stopping.

That means a transparent object doesn't look very different from the surrounding air or water. You don't see it —you see the things

behind it.

   To become transparent, an animal needs to keep its body from absorbing or scattering light. Living materials can stop light because they

contain pigments(色素) that absorb specific colors of light. But a transparent animal doesn't have pigments, so its tissues won't absorb

 light. According to  Johnsen, avoiding absorption is actually easy. The real challenge is preventing light from scattering.

Animals are built of many different materials—skin, fat, and more—and light moves through each at a different speed. Every time light

moves into a material with a new speed, it bends and scatters.Transparent animals use different tricks to fight scattering. Some animals are

simply very small or extremely flat. Without much tissue to scatter light, it is easier to be see--through. Others build a large, clear mass of

 non-living jelly-lie(果冻状的)material and spread themselves over it .

    Larger transparent animals have the biggest challenge, because they have to make all the different tissues in their bodies slow down light 

exactly as much as water does. They need to look uniform. But how they're doing it is still unknown. One thing is clear for these larger animals, staying transparent is an active process. When they die, they turn a non-transparent milky white.

    Our room was on the second floor but you could still hear the roar of the ocean and see the stars at night. I used to take long walks along the water. The food in town was wonderful and the people were very friendly. The area was very quiet and peaceful, and fairly deserted.

    The last evening of our vacation, however, we all heard strange footsteps following closely behind us as we were walking up to our room in the holiday centre. We turned around and noticed a fairly young man moving very rapidly across the beach and getting closer to us. He was tall and wore a baseball cap. We couldn't see his face and he was approaching us very rapidly. The man's actions made my dad very nervous. Dad warned us that we'd better try to make it to our hotel room as quickly as possible. I didn't like my dad's voice; I could hear fear in it. It was late and we were all alone. We didn't have any cell phones on us. I never saw Dad as worried as he was then and I knew that something was terribly wrong. The sense of fear started to overwhelm Mom and me. We had had such a good time in town. Now, the night was rapidly turning into a dangerous situation.

    We could hear the man's footsteps getting closer. Dad's face was almost pale. The so-called intruder (侵入者) had moved nearer and nearer when all of a sudden, the nearby vending (自动贩卖) machine started going crazy and spitting out cans of soda! The noise actually scared the intruder and he ran out of sight. My parents were shaking, but we all turned around to see who had put money into the vending machine downstairs, and actually saved us, but no one was around at all. Not a soul.

    It's one vacation I will never forget.

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A

    Four Must-See Route 66 (66号公路) Attractions

    The United States is full of odd roadside attractions. Route 66 is home to some of the oldest and most known attractions of them all. Here are four attractions you should see along the Mother Road:

    ⒈Paul Bunyan and a Hot Dog

    Route 66 travelers pass by many fiberglass giants（巨人）right along the road. These giants were a popular form of advertising in the 1960s.Many of them stood in front of service stations. They held car parts, such as mufflers. The collection of Route 66 giants became known as “Muffler Men”. Businesses hoped the strange statues would get travelers' attention.

    The first fiberglass giant was a “Paul Bunyan” figure, built in the early 1960s. It's said that Paul Bunyan is a famous wood worker.

    ⒉Crown Candy Kitchen and Jamaica Ray

    Crown Candy Kitchen has been serving Route 66 travelers from the very beginning. It is just a few short blocks from the 66 path through St. Louis, Missouri. The family-run soda fountain shop opened more than 100 years ago, and has been making candies and meals ever since.

    On weekends, people sometimes wait in line for a table at Crown Candy for over an hour. Luckily there is free entertainment right outside. Jamaica Ray, a local folk artist, creates unusual sculptures.

    ⒊The World's Largest Rocking Chair

    Fanning, Missouri, is home to one of the strangest Route 66 attractions. Just off the road sits an almost 13-meter-tall rocking chair.

    The structure was completed in 2008 on the first of April, or April Fool's Day. At one time the chair actually rocked. But officials decided it had to be still to be safe for ever. People are not permitted to climb the chair. We think, however, that it probably happens once in a while, when no one is watching.

    ⒋Big Texan's Steak Challenge

    Few places better represent the common expression “Everything's Bigger in Texas” than the Big Texan Steak Ranch. Since 1960.it has appealed to travelers with big appetites and a big love of beef.

    It is hard to miss the huge yellow restaurant or the giant cow statue that sits out front. The cow advertises Big Texan's special deal, and what has made this steak ranch famous: a “free” 72-ounce（英两）or 2-kilogram steak. There is one trick: the steak is only free if you can eat the entire thing in one hour.

    A special table is in the middle of the restaurant for the daring diners who accept the challenge. Since 1990, more than 9,000 diners have eaten the entire 2-kilogram steak.

    Businesses are finding more uses for Virtual Reality (VR) as the technology develops. VR is no longer only for gaming or enjoyment. An American company called Blue Goji is using VR to improve one's health by making exercise more fun.

    Blue Goji has offices in Austin, the capital of Texas. The company showed its cardiovascular (心血管的) workout machine, called the Infinity treadmill (跑步机), at the recent South by Southwest festival, an event held every year in Austin.

    A person using the treadmill wears a virtual reality headset when exercising. Before starting, the user tightens a belt to prevent falls. Then, the user plays a VR game while running on the machine. The game can transport the user into the virtual world, where he or she can be racing against virtual people.

    Recently, Leonardo Mattiazzi tested the Infinity treadmill. Mattiazzi said he had a strong feeling to actually get running and do something that pushed his limits. He said the experience was more interesting than running inside the gym without actually going anywhere.

    Constam said the active use of virtual reality helps solve a common problem while wearing a VR headset. She noted that a lot of VR experiences cause motion sickness because people are in motion during the game, but not moving in real life. But when the user is moving on the treadmill and in the game, the chances of motion sickness are reduced.

    However, users who tested the treadmill while wearing the VR headset each had a different experience. Constam said there generally is a learning curve for VR. The first time users feel lost, but "the more you do it, the more you get used to it," she said. Mark Sackler was a first time user. He said he felt a little sick at one point during the game. But he thought the experience was surprisingly realistic.

    After carefully studying the users' experiences, Blue Goji plans to make the treadmill available to the public in 2019.

    Hilary Smith belonged to a good family. But by the age of twenty, he had spent all the money the good old family had. He then had some trouble with the bank and was put in prison. He escaped from the prison and ran to Australia without delay.

    Hilary did not like Australia and Australia did not like Hilary. What he could do seemed to be one of two things: die or work. Then he remembered that he was not alone in the world. He had an aunt.

    She was his father's only sister, but his father used to say she brought no glory to the family. Hilary, of course, tried to discover what she had done. It seemed that she had failed to marry a nobleman. Instead, she had chosen a husband who was connected with "trade". Of course as soon as she became "Mrs. Parks", her brother considered her dead. Later on, Mr. Parks died and left her a lot of money; but that did not bring her back to life in her brother's opinion.

    Hilary discovered his aunt's address. Fortunately she remained faithful and honest to him even after she fell ill. So Hilary's star shone again, and soon he moved into her house and lived as comfortably as a sailor who had just reached harbor. He had only about six pence in his pocket.

    One thing was soon clear: his aunt was seriously ill, and nothing could cure her illness. Hilary was very worried. Fate had found a home for him, and was now going to throw him out of it. There was only one thing that could save him: her will.

    "Will?" she said, "yes, I have made one. That was when I was a girl and had not much money. I left all my money to some religious people."

    "Didn't you make another will when you were married?" Hilary asked.

    His aunt shook her head. "No," she said in a low voice, "There was no need. When I finally had a lot of money, I found I had no relations."

    On the next day he went to the public library and examined a book of law. It told him what he already believed. When a woman is married, an earlier will loses its value. A new will must be made. If no new will is made, the money goes to the nearest relation. Hilary knew that he was his aunt's only relation. His future was safe.

    After a few months had passed, Hilary's problems became serious. He badly needed money. He had expensive tastes, and owed a lot of money to shopkeepers. They trusted him because his aunt was rich, but the debt was terrible.

    Unfortunately his aunt did not want to discuss money matters at all. In the end they had a quarrel about the small amount of ten pounds. Hilary was not very angry. He began to wonder about a new problem. Was it kind to want his aunt to live any longer? Was it not better for her to die now? While he was considering what to do, his aunt told him that she was going to send for her lawyer. So she was going to make a new will, Hilary thought. She might leave all her money to someone else. Soon he reached a clear decision. He must do a great kindness to the poor old woman.

    One night when the old servant who had been nursing his aunt went off, he doubled the amount of some medicine. The total amount was too great and it could just put her to sleep forever.

    "Thank you," his aunt took the glass from his hand with a grateful look." I want, more than anything, to sleep, and never to wake up again. Is that what you wish, Hilary? Don't blame me if I have some doubts about what you intended to do. Sick people get these ideas, you know. One thing I ought to explain to you. Mr. Parks never married me. He already had a wife and couldn't marry again. That made your foolish father very angry with me...Well, if I am alive tomorrow, I shall make another will in your favor. If I die tonight, you'll get nothing...No, Hilary, don't try to take the glass away. If you do that, I shall know and I don't want to know. Good night, Hilary."

    Then, very carefully, she raised the glass to her mouth and drank.

    If you wear glasses, chances are you are smarter. Research published in the famous British journal Nature Communications has found that people who displayed higher levels of intelligence were almost 30 percent more likely to wear glasses.

    The scientists studied the genes of thousands of people between the ages of 16 and 102.The study showed intelligence can be connected to physical characteristics. One characteristic was eyesight. In out of 10 people who were more intelligent, there was a higher chance they needed glasses. Scientists also said being smarter has other benefits. It is connected to better health.

    It is important to remember these are connections which are not proven causes. Scientists call this correlation. Just because something is connected to something else does not mean one of those things caused the other. And it's worth noting that what constitutes intelligence is subjective and can be difficult, if not impossible, to measure.

    Forget genes though. Plenty of proof shows wearing glasses makes people think you are more intelligent, even if you do not need glasses. A number of studies have found people who wear glasses are seen as smarter, hard-working and honest. Many lawyers use this idea to help win their cases. Lawyer Harvey Solves explained this. Glasses soften their appearance. He said sometimes there has been a huge amount of proof showing that people he was defending broke the law. He had them wear glasses and they weren't found guilty.

    Glasses are also used to show someone is intelligent in movies and on TV. Ideas about people who wear glasses have begun to shift. People who do not need glasses sometimes wear them for fashion only. They want to look worldly or cool. But not everyone is impressed by this idea, though. GQ magazine said people who wear glasses for fashion are trying too hard to look smart and hip (时髦的). However, that hasn't stopped many celebrities from happily wearing glasses even if they do not need them. Justin Bieber is just one high-profile fan of fashion glasses.