When she looked ahead，Florence Chadwick saw nothing but a solid wall of fog.Her body was numb (麻木的)．She had been swimming for nearly sixteen hours.

    Already she was the first woman to swim the English Channel in both directions.Now，at age 34，her goal was to become the first woman to swim from Catalina Island to the California coast.

    On the morning of July 4th，1952，the sea was like an ice bath and the fog was so thick that she could hardly see her support boats.The wind was strong and it was raining heavily.Against the cold water of the sea，she struggled on—hour after hour.Millions of people at home were watching her in front of the television.

    In one of the boats，her mother and her trainer tried their best to encourage her.They told her it wasn't much farther.But all she could see was fog.They urged her not to give up.She never had...until then.With only a half mile to go，she asked to be pulled out.

    After thawing her cold body several hours later，she told a reporter，“Look，I'm not excusing myself，but if I could have seen land I might have made it.” It was not tiredness or even the cold water that defeated her.It was the fog.She was unable to see her goal.

    Two months later，she tried again.This time，despite the same thick fog，she swam with all her strength and her goal clearly pictured in her mind.She knew that somewhere behind that fog was land and this time she made it! Florence Chadwick became the first woman to swim the Catalina Channel!  

    See a cell phone cover that you like on Taobao? Forget about placing an order, paying the bill online and waiting for days for it to be delivered to you. In the near future, you'll be able to get it in minutes just by hitting "print" on your computer. You might find it hard to believe that you could actually "print" an object as you would a picture. But it is not that hard to understand how it would work. Just as a traditional printer sprays (喷) ink onto paper line by line, modem 3-D printers spread material onto a surface layer by layer, from the bottom to the top, gradually building up a shape.

    Instead of ink, the materials the 3-D printer uses are mainly plastic, resin (树脂) and certain metals. The thinner each layer is — from a millimeter to less than the width of a hair —the smoother and finer the object will be. This may sound like a completely new technology, but the truth is that 3-D printing has been around since the late 1980s. Back then, it was barely affordable for most people, so few knew about it.

Last year, though, saw a big change in the 3-D printing industry — printers became much cheaper. For example, 10 years ago a desktop 3-D printer might have cost £20,000, while now they cost only about £ 1,000, according to the BBC. Taken out of the factory and introduced to more diverse and common uses, 3-D printing can create just about anything you can think of — flutes (笛子), bikinis, jewelry, aircraft parts and even human organs. In fact, scientists from Cornell University in New York have just made an artificial ear using a 3-D printer, according to Science Daily. The fake ear looks and acts exactly like a natural one.

    However, as 3-D printing becomes more common, it may bring about certain problems —such as piracy. "Once you can download a coffee maker, or print out a new set of kitchen utensils (餐具) on your personal 3-D printer, who will visit a retail (零售的) store again?", an expert in 3-D printing told Forbes News. Even more frightening, what if anyone in the world could use a 3-D printer to print out a fully functioning gun?

阅读理解

    Although computers used to be large, expensive and difficult to use, they have been made smaller, cheaper and easier to use. As a result, more people have been buying computers for their homes and businesses. They are used to record information and make difficult things easy.

    Let's look at some of the many ways computers may affect(影响) your life.

    Want to get the best treatment at hospitals? Your doctors at hospitals have been greatly helped by computers to get information about patients. It is possible for doctors from different hospitals to read the records of patients, discuss them and make decisions on the best treatment. It would, at one time, take them hours and days to do so.

    Want to talk to your friends both at home and abroad? Then it's necessary to connect your computer to the Internet and set up your own e-mail letter box. You can then collect and send mails in seconds. It will be a waste of time and money to post your letters.

    Want to get advice from Michael Jordan on how to play basketball like a NBA super star? Now it is possible to find out what it is on the Internet.

    But if you think you have entered the information age because you have the chance to use the Internet, you are wrong. The reason is quite a simple one: over 98 percent of the information on the Internet is in English. The information on-line won't be helpful to you unless you can use English freely.

    Why do some people live to be older than others? You know the standard explanations: keeping a moderate diet, engaging in regular exercise, etc. But what effect does your personality have on your longevity(长寿)? Do some kinds of personalities lead to longer lives? A new study in the Journal of the American Geriatrics Society looked at this question by examining the personality characteristics of 246 children of people who had lived to be at least 100.

    The study shows that those living the longest are more outgoing, more active and less neurotic (神经质的) than other people. Long-living women are also more likely to be sympathetic and cooperative than women with a normal life span. These findings are in agreement with what you would expect from the evolutionary theory: those who like to make friends and help others can gather enough resources to make it through tough times.

    Interestingly, however, other characteristics that you might consider advantageous had no impact on whether study participants were likely to live longer. Those who were more self-disciplined, for instance, were no more likely to live to be very old. Also, being open to new ideas had no relationship to long life, which might explain all those bad-tempered old people who are fixed in their ways.

    Whether you can successfully change your personality as an adult is the subject of a longstanding psychological debate. But the new paper suggests that if you want long life, you should strive to be as outgoing as possible.

    Unfortunately, another recent study shows that your mother's personality may also help determine your longevity. That study looked at nearly 28,000 Norwegian mothers and found that those moms who were more anxious, depressed and angry were more likely to feed their kids unhealthy diets. Patterns of childhood eating can be hard to break when we're adults, which may mean that kids of depressed moms end up dying younger.

    Personality isn't destiny, and everyone knows that individuals can learn to change. But both studies show that long life isn't just a matter of your physical health but of your mental health.

    The city of San Francisco is a wonderful tourist attraction that offers many different things to see and do. The best way for a traveler to get a good look at the city is to take one of the many different tours there

    Walk to Tour the City

    When touring the city by walking, you aren't going to walk much. What's more, there are far more benefits. This kind of tour allows you to see as many buildings of the city as possible. A tour of the city on foot usually focuses on a more localized neighborhood level, which can be very interesting in a number of different ways.

    Hit the Waters of San Francisco Bay

    The waters of San Francisco Bay have played an important role in the city's development over the last century. Touring San Francisco from the water is completely unique way for you to see this wonderful city.

    Take a Bus Tour

    If you want to see a wide variety of attractions from all over the city, one of the best things you could do is to book a tour through our company that offers services here. A bus tour of San Francisco is one of the most complete ways to experience the city

    Tour San Francisco From the Air

    While it is one of the most expensive ways to see San Francisco, touring the city from the air is one of the most unique and exciting ways to see the city. Seeing the city from high above allows you to get a full view of the city as tour guides point out attractions from high above. If you do decide to tour San Francisco by air, you'll be creating memories that you won't forget forever.

    We are a travel agency providing high-quality services and discounts. For more information, please click here.

    The United States of America is mainly an English-speaking country. The majority of the population speak English as their native language. Besides, education, social activities, etc. are conducted in English. Across but for the most part, Americans speak one common language. This language is sometimes called American English.

    However, not everyone in the USA is a native speaker of English. Most immigrants (移民)are speakers of other languages. There are hundreds of communities around the USA where English is not the most commonly used languages. Chinese, Italian, German, Greek, Spanish and French are all spoken in various communities in the USA. Spanish is the second most commonly spoken language after English. It is widely spoken in New York and across the southern part of the country. For speakers of other languages, learning English is important, but teaching people to speak English as a second language was given little attention. Non-English speakers were expected to "pick up" the language by meeting with others in public. Recently, this has changed.

    Today, most large public schools and community colleges have ESL(English as a Second Language )programs; American English teachers feel that English students should learn the language the way they will use it. Therefore, ESL programs offer different English lessons to different students. Some programs teach students to communicate in English in public. Other programs teach the kind of English people who will need for their jobs. American ESL instructional methods do not lay emphasis on grammar or translation, but on the importance of communication. The goal is to get the English learners to learn by using the language.