Here is an astonishing and significant fact: Mental work alone can't make us tired. It sounds absurd. But a few years ago, scientists tried to find out how long the human brain could labor without reaching a stage of fatigue(疲劳). To the amazement of these scientists, they discovered that blood passing through the brain, when it is active, shows no fatigue at all! If we took a drop of blood from a day laborer, we could find it full of fatigue toxins(霉素) and fatigue products. But if we took blood from the brain of an Albert Einstein, it would show no fatigue toxins at the end of the day.

    So far as the brain is concerned, it can work as well and swiftly at the end of eight or even twelve hours of efforts as at the beginning. The brain is totally tireless. So what makes us tired?

    Some scientists declare that most of our fatigue comes from our mental and emotional(情感的) attitudes. One of England's most outstanding scientists, J. A. Hadfield, says, “The greater part of the fatigue from which we suffer is of mental origin. In fact, fatigue of purely physical origin is rare.” Dr. Brill, a famous American scientist, goes even further. He declares, “One hundred percent of the fatigue of a sitting worker in good health is due to emotional problems.”

    What kinds of emotions make sitting workers tired? Joy? Satisfaction? No! A feeling of being bored, anger, anxiety, tenseness, worry, a feeling of not being appreciated—those are the emotions that tire sitting workers. Hard work by itself seldom causes fatigue. We get tired because our emotions produce nervousness in the body.

    University Room Regulations

    Approved and Prohibited Items

    The following items are approved for use in residential rooms: electric blankets, hairdryers, personal computers, radios, televisions and DVD players. Items that are not allowed in student rooms include: candles, ceiling fans, fireworks, waterbeds, sunlamps and wireless routers. Please note that any prohibited items will be taken away by the Office of Residence Life.

    Access to Residential Rooms

    Students are provided with a combination(组合密码) for their room door locks upon check-in. Do not share your room door lock combination with anyone. The Office of Residence Life may change the door lock combination at any time at the expense of the resident if it is found that the student has shared the combination with others. The fee is $25 to change a room combination.

    Cooking Policy

    Students living in buildings that have kitchens are only permitted to cook in the kitchen. Students must clean up after cooking. This is not the responsibility of housekeeping staff. Kitchens that are not kept clean may be closed for use. With the exception of using a small microwave oven(微波炉) to heat food, students are not permitted to cook in their rooms.

    Pet Policy

    No pets except fish are permitted in student rooms. Students who are found with pets, whether visiting or owned by the student, will suffer an initial fine of $100 and a continuing fine of $50 a day per pet. Students receive a written notice when the fine goes into effect. If, one week from the date of written notice, the pet is not removed, the student is referred to the Student Court.

    Whether you are young or young at heart, it is never too late to change, or take in some new and better practices into your daily life. Here are some wise lessons that I wish I knew when I was younger.

    I used to be worried about what others thought of me. Finally, I changed. Remember that if you're wasting too much time looking for respect(尊重) from others, then you will not have time to finish all you desire(期望).Everyone has an opinion, but in fact others' opinions about you are based more on their history and perceptions(观念) than anything you're actually doing. So depend on your own assessment(评估) of you rather than others'.

    Enjoy every moment of today. Don't wait to do or enjoy anything. Don't tell yourself you will do it tomorrow. If it is important to you, then do it today. Pay attention to what is happening now, the task at hand and all the choices you make today, big and small. Our future is set by what we decide and do today.

    What happened yesterday is over. You can not change it. So let it go. Don't waste your energy considering anger or unhappiness. It only stops you from moving forward in life.

    Look for the good in people. Celebrate the happy moments, big and small. Search for the chances for growth. Give helpful encouragement rather than unwanted criticism (批评). Be helpful whenever possible.

    In a word, life is serious but you can still be delighted and hopeful. Otherwise, what's the point?

    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.

    The World Happiness Report, a United Nations agency report, measures (估量) how happy people are, and why. Norway is the happiest place on earth—beating neighbour Denmark from the number one position.

    Denmark, Iceland, Switzerland and Finland are among the top five, while the Central African Republic came last. Western Europe and North America took up most of the places at the top of table, with the US and UK at 14th and 19th respectively.

    The World Happiness Report mainly depends on asking a simple question of more than 1,000 people every year in more than 150 countries. “Imagine a ladder, with steps numbered from 0 at the bottom to 10 at the top,” the question asks. “The top of the ladder is the best possible life for you and the bottom of the ladder is the worst possible life for you. On which step of the ladder would you say you personally feel you stand at this time?”

    The average (平均的) result is the country's score—from Norway's 7.54 to the central African Republic's 2.69. But the report also tries to explain why one country is happier than another. It looks at reasons including economic strength, social support, freedom of choice, and generosity.

    This year's report also has a text titled “restoring (恢复) American happiness”, which examines why happiness levels in the United States are falling, despite continually-increasing economic improvement. “The United States can and should raise happiness by solving American's social problems—rising inequality and distrust—rather than focusing mainly on economic growth,” the authors said.

    Jeffrey Sachs, the director of the Sustainable Development Solutions Network, which published the report, said President Donald Trump's policies were likely to make things worse.

Recently I read Nineteen Eighty-Four,a novel by George Orwell set in a state where even the language they use is controlled.Adjectives are forbidden and instead they use phrases such as "ungood","plus good" and "double plus good" to express emotions.As I first read this I thought how impossible it would be in our society to have such vocabulary.However,the more I thought about it,the more I realised in its own way it's already happening.I type messages to my friends and alongside each is the emoji.I often use it to emphasise something,or to not seem too serious,or because this specific GIF conveys my emotions much better than I ever could using just words.And I wonder,with our excessive use of emojis,are we losing the beauty and diversity of our vocabulary?

English has the largest vocabulary in the world,with over one million words,but who's to say what it'll be like in the future?Perhaps we will have a shorter language,full of saying "cry face" if something sad happens or using abbreviations(缩写) like LOL(laugh out loud) or BRB(be right back) instead of saying the full phrase.So does this mean our vocabulary will shrink?Is it the start of an exciting new era?Will they look back on us in the future and say this is where it all began—the new language?Or is this a classic case of the older generations saying,"Things weren't like that when I was younger.We didn't use emoticons to show our emotions"?

Yet when you look back over time,the power of image has always been there.Even in the prehistoric era they used imagery to communicate,and what's even more incredible is that we are able to analyse those drawings and understand the meaning of them thousands of years later.Pictures have the ability to transcend time and language.Images,be it cave paintings or emojis,allow us to convey a message that's not restrictive but rather universal.