Life may have evolved on at least three planets within a newly discovered solar system 39 light years from Earth. Astronomers at the NASA have discovered no less than seven roughly Earth-sized worlds orbiting a dwarf star in the system. Scientists had previously identified a tiny number of "exoplanets", which are believed to have the qualities needed to support life. However, the new system contains an unprecedented(前所未有) number of Earth-sized, probably rocky planets, and is being acknowledged as an "accelerated leap forward" in the search for extraterrestrial (外星球的)life.

    Three of the new planets are said to be particularly promising because there might exist oceans. Thomas Zurbuchen, associate administrator of NASA, told a press conference in Washington: "This gives us a hint that finding a second Earth is not a matter of 'if', but 'when'."

    The planets were discovered using NASA's Spitzer Space Telescope, which was able to track how fast each of the planets crossed the star Trappist-l and completed an orbit. From this the research team calculated how far the planets were from their star, and therefore how likely they are to be habitable.

    NASA's Hubble Space Telescope is already being used to search for atmospheres around the planets. Future telescopes, including the proposed European Extremely Large Telescope and the James Webb Space Telescope, may be powerful enough to discover markers of life, such as oxygen in the atmospheres of exoplanets.

    Astronomers believe there could be as many as 40 billion potentially habitable worlds in our galaxy, the Milky Way. Prof Zurbuchen said that now was a "gold-rush phase" in the search for these exoplanets.

根据短文内容，选择最佳答案，并将选定答案的字母标号填在题前括号内。

    Australia is a big country, but it is easy to get around. The untouched beaches that go for miles and deserts that touch the horizon(地平线) are just there, waiting to be reached and explored. You can explore the big country in different ways.

Air

    Flying is the best way to cover large distances in a short time. You can spend more time on the Australia's landscapes(陆地风光) and relaxing lifestyle. Moreover, competition among airlines makes great flying fees available for you.

Drive

    Australia has a big network of well-kept roads and some of the most beautiful touring routes in the world. You have no trouble finding car rental companies at major airports, central city and suburbs(怒火).

Bus

    Bus travel in Australia is comfortable, easy and cheap. Buses generally have air conditioning, reading lights, adjustable(可凋) seats and videos. Services are good for everyone, frequent.

Rail

    Train travel is the cheapest and gives you an insight into Australia's size, all from the comfort of your carriage. Scheduled services are a great way to get quickly between our cities and regional centers.

Ferry(轮渡)

    The Spirit of Tasmania runs a passenger and vehicle ferry service between Melbourne and Tasmania nightly. Extra services are running during summer rush hours. Sea-link ferries connect South Australia and Kangaroo Island several times a day. Ferries connect suburbs in our capital cities.

    Besides all of above, you can also experience some of the longest tracks and trails in the world in central Australia-impressive journeys of a thousand kilometers or more that can take several weeks to complete.

    Everyone wants to win, and everybody knows it. Take the case of Olympic athletes, who train hard each day for years to reach the top of their sport and hopefully win a gold medal. Since every competitor's goal is to win, we assume that the silver medalists would be less happy than gold-medal winners, but still happier than those in third place. Common sense says that our levels of happiness should have something to do with our levels of achievement – except that often this isn't the case.

    Researchers found that bronze medalists actually appeared on the whole to be happier than silver medalists. How could that be? The answer, in a word, is gratitude. Silver medallists, who compared themselves to the gold medalists, experienced disappointment at having been close to winning the gold, but falling short. The bronze medalists, on the other hand, were thankful to have won a medal at all, comparing themselves to all those who didn't even reach the Olympic platform.

    If happiness, then, is the aim of life, perhaps our achievement-centered culture is getting it all backwards. We focus on what we want rather than on what we have. We forget to be grateful, and as a result we forget to be happy.

    We're from a culture that teaches us to envy others – another person achievements – and that is always looking forward to what comes next. Yet in a better society, might we not look at what all of our earlier nexts have already earned us?

    I encourage any person who struggles with frustration （挫折）in their life to take out a notebook and a pen each evening before bed, and to write down all the things that they have gratitude for. It's not a cure for dissatisfaction, to be sure, but many people quickly discover that, when they actually stop to think about it, they have things pretty good and happiness comes.

    Those bronze medalists, after all, can't be wrong.

    During the past Spring Festival, many children may have received red packets from their families. But Xing Pu, a 40-year-old economist, is asking the government to give red packets to every Chinese citizen.

    Xing suggested the government give out 1,000 yuan to each Chinese since the government income has increased rapidly in recent years. He said his suggestion would allow everyone to directly enjoy the fruits of the country's economic success, help the lower-income groups deal with rising prices and increase consumption (消费) around the country.

    Recent years have seen the government carry out a series of pro-poor (扶贫) and pro-rural (惠农) policies, including increasing spending on public healthcare and calling off the agricultural tax. But the lower-income group still needs more help while being hit hard by an 11-year high in prices and recent snowstorms.

    Xing said while making the draft, he has borrowed many ideas from practices in countries like the United States and Singapore. Earlier this year, the governments of the two nations offered money to their citizens as the result of a surplus in government income. As for in China, "We can even encourage the rich to donate their 1,000 yuan red packet to the poor," said Xing.

    Although Xing's suggestion has gained wide support among ordinary Chinese on the Internet, many other economists criticized it as unpractical. Even Xing himself admitted he made the suggestion without any careful calculation. But they agreed with Xing's point that the growing economic pie should be shared among the people.

    "To better use the increase of money, handing out money is not a solution that holds good for all time. It could be better to improve the public service or cut the price of energy used in daily life," said QiaoXinsheng, an economic professor.

    You probably know who Marie Curie was, but you may not have heard of Rachel Carson. Of the outstanding ladies listed below，who do you think was the most important woman of the past 100 years?

Jane Addams (1860－1935)

    Anyone who has ever been helped by a social worker has Jane Addams to thank. Addams helped the poor and worked for peace. She encouraged a sense of community (社区) by creating shelters and promoting education and services for people in need. In 1931，Addams became the first American woman to win the Nobel Peace Prize.

Rachel Carson (1907－1964)

    If it weren't for Rachel Carson, the environmental movement might not exist today. Her popular 1962 book SilentSpring raised awareness of the danger of pollution and the harmful effects of chemicals on humans and on the world's lakes and oceans.

Sandra Day O'Connor (1930－present)

    When Sandra Day O'Connor finished third in her class at Stanford Law School, in 1952, she could not find work at a law firm because she was a woman. She became an Arizona state senator (参议员) and，in 1981, the first woman to join the U．S. Supreme Court. O'Connor gave the deciding vote in many important cases during her 24 years on the top court.

Rosa Parks (1913－2005)

    On December 1, 1955, in Montgomery, Alabama, Rosa Parks would not give up her seat on a bus to a white passenger. Her simple act landed Parks in prison. But it also set off the Montgomery bus boycott. It lasted for more than a year, and kicked off the civil ­ rights movement. “The only tired I was, was tired of giving in，”said Parks.

    We lived in a quiet neighborhood. One evening I heard a loud crash. Earlier my wife had asked me to the store for soft drinks. My teenage daughter Holly practiced her driving, so I sent her to the store in my truck.

    At dinner my son talked about how much he liked my truck. I enjoyed having it, but I said: "My heart is not set on that truck. I like it but it is just metal and won't last forever. Never set your heart on anything that won't last. "

    After hearing the loud noise, the whole family ran outside. My son shouted: "Holly crashed your truck."

    The accident took place in my own driveway. Holly had crashed my truck into our other vehicle(交通工具), the family van. In her inexperience, she had confused the brake(刹车) and the gas pedal(油门). Holly was unhurt physically, but she was crying, "Dad, I'm sorry. I know how much you love this truck." I held her in my arms as she cried.

    I still remembered how sad Holly was the night she crashed our truck, and how I comforted her. When Holly thinks back on her life, I want her to know that I love her a thousand times more than any piece of property(财产).

    I repaired the van, but the dent(凹痕) in my truck is still there today. Every day it reminds me of what really matters in my life.