Have you ever wanted to travel back in time? What about traveling into the future? There's an easy way to do it. One way you can make a time travel journey is by writing a letter to your future self to be opened in the future. To your future self, the letter will be a visit from the past. 

    What can be gained by writing a letter to yourself? Depends on how good your letter is. You have the chance to say something to your future self. What would you want to say? You'll be able to talk to yourself 5,10,15 years down the road. There may be instructions for your future self, or you may have goals that you will want to reach.

    There are a lot of things you could include in your letter or letters to yourself. The more you include, the better the letter will be to you. Be creative with what you put in your letter. Include a picture of yourself or family to show the period from which the letter came.

    You can store your letter in many different ways. You can give your letter to a friend or family member to keep and mail to you. If you can get others to take part, have them write letters to themselves as well and ask someone to be the letter holder until it's time to send the letters. You can also use a service online to store your letter and e-mail it to you. Ready to write to yourself two and a half years down the road?

    If you ask people to name the one person who had the greatest effect on the English language, you will get answers like "Shakespeare," "Samuel Johnson," and "Webster," but none of these men had any effect at all compared to a man who didn't even speak English-William the Conqueror.

    Before 1066, in the land we now call Great Britain lived peoples belonging to two major language groups. In the west-central region lived the Welsh, who spoke a Celtic language, and in the north lived the Scots, whose language, though not the same as Welsh, was also Celtic. In the rest of the country lived the Saxons, actually a mixture of Anglos, Saxons, and other Germanic and Nordic peoples, who spoke what we now call Anglo-Saxon (or Old English), a Germanic language. If this state of affairs had lasted, English today would be close to German.

    But this state of affairs did not last. In 1066 the Normans led by William defeated the Saxons and began their rule over England. For about a century, French became the official language of England while Old English became the language of peasants. As a result, English words of politics and the law come from French rather than German. In some cases, modem English even shows a distinction(区别)between upper-class French and lower-class Anglo-Saxon in its words. We even have different words for some foods, meat in particular, depending on whether it is still out in the fields or at home ready to be cooked, which shows the fact that the Saxon peasants were doing the farming, while the upper-class Normans were doing most of the eating.

    When Americans visit Europe for the first time, they usually find Germany more "foreign" than France because the German they see on signs and advertisements seems much more different from English than French does. Few realize that the English language is actually Germanic in its beginning and that the French influences are all the result of one man's ambition.

    When you live in total messiness—cookies in your pants draws, and some old New Yorkers or apple seeds in your bed—it's hard to know where to look for when you lose your keys. The other day, after two weeks of searching, I found my keys in the refrigerator. I can't say I was surprised. But I was surprised when I was diagnosed with ADHD(多动症), when I was a junior at Yale.

    According to a new study, 11% of school-age children have received an ADHD diagnosis, a 16% increase since 2007. And rising diagnoses mean rising treatments—drugs like Adderall are more accessible than ever. However, the consequences of misuse and abuse of these drugs are dangerous.

    Yet also harmful are the consequences of ADHD undiagnosed, an all-too-common story for women like me, who have symptoms, like disorganization and forgetfulness, which look different from those typically expressed in males.

    Dr. Ellen, author of Understanding Girls with ADHD, has found around 4 million females with ADHD are not diagnosed. "The main reason is that the diagnostic criteria were developed based on those hyperactive（过度活跃）young boys taken to clinics, making it difficult for girls to be diagnosed unless they behave like hyperactive boys." Ellen says.

    Besides, the idea that young women actually have ADHD often causes skepticism. As a top student, I didn't believe my diagnosis at first. My friends were also confused, and rather certain my doctor was misguided.

    "Often, if girls are smart or in supportive homes, symptoms are masked," Dr.Ellen says. "Girls will hide their inability to meet social expectations. They see their trouble organizing, and concentrating as character flaws(缺陷)."

    These years, I am both embarrassed and exhausted by my struggles to keep track of objects, but drug has helped it and made it more bearable.

Scientists at the Department of Energy's Lawrence Berkeley National Laboratory and the California Institute of Technology have-in just two years-nearly doubled the number of materials known to have potential for use in solar fuels.

They did so by developing a process that promises to speed the discovery of commercially viable (商业可行性) generation of solar fuels that could replace coal, oil, and other fossil fuels.

Solar fuels, a dream of clean-energy research, are created using only sunlight, water, and carbon dioxide. Researchers are exploring a range of possible target fuels, but one possibility is to produce hydrogen by splitting water.

Each water molecule (分子) consists of one oxygen atom and two hydrogen atoms. The hydrogen atoms are extracted, and then can be reunited to create highly flammable hydrogen gas or combined with CO 2 to create hydrocarbon fuels, creating a plentiful and renewable energy source. The problem, however, is that water molecules do not simply break down when sunlight shines on them-if they did, the oceans would not cover most of the planet. They need a little help from a solar-powered catalyst (催化剂).

To create practical solar fuels, scientists have been trying to develop low-cost and efficient materials that perform the necessary chemistry using only visible light as an energy source.

A new method was developed through a partnership between the Joint Center for Artificial Photosynthesis (JCAP) and Berkeley Lab's Materials Project, using resources at the Molecular Foundry and the National Energy Research Scientific Computing Center (NERSCC). JCAP focused on developing a cost-effective method of turning sunlight, water, and carbon dioxide into fuel. It is led by Caltech with Berkeley Lab as a major partner. The Materials Project is a program based at Berkeley Lab that aims to remove the guesswork from materials design in a variety of applications.

"What is particularly significant about this study, which combines experiment and theory, is that in addition to identifying several new compounds for solar fuel applications, we can also learn something new about the basic electronic structure of the materials themselves." says Neaton, the director of the Molecular Foundry.

I'm standing on Rio's beach, one of the most famous 1 of sand. In this lively, multicultural country, the beach is not just a place;it's a state of mind—a way of thinking and living. 

Every Brazilian has his or her own ideas of the perfect beach, 2 to tell you where to find it. I'm happy to take their advice but my ultimate goal is to find my own dream beach. First, I go to Prainha's beach 3 by a row of perfect palm trees, moving softly in the ocean breeze. Its beauty is magnificent-its perfect graceful lines are like something in a 4 . But for me, it's somewhat too perfect. I am searching for something a bit 5 . 

I continue my search heading north to a legendary beach: Jeri. As an international destination, it attracts visitors from Tokyo to Toronto. Luckily, Jeri hasn't been 6 by tourists mostly because of its isolated(偏远的)location—at least five hours from any airport. I take a beach buggy(沙地车), driving for three hours. The boats lie on their sides while nets 7 to dry on lines between fishermen's houses. Peaceful and beautiful! How can it possibly get any better? I 8 . 

My final stop is the islands of Fernando, 9 a few hundred kilometers out in the Atlantic. They once were used as a prison and later by the army. Today, they are a national park and UNESCO World Heritage Site, 10 with birds and sea life. The beach there is a perfect 11 of sand, sea, and sky. The water is pale blue and warm, alive with colorful fish, 12 , and other marine life; the sand is the color of 13 . In the rocks and strong winds that 14 come in from the Atlantic, there is the wilderness I was seeking. Finally, I've found the beach of my dreams. I 15 my toes in the sand deeply and imagine I can hold on to this place forever.

Must-read New Fiction Books

We all have a few tried-and-true fiction favorites, but there's something special about a brand-new, hot-off-the-press novel. Whether it's your favorite author's new release or a new writer's first work, great fiction books make the perfect escape from ordinary life. That's why we've rounded up a list of the best new books released in February.

Age of Gold by Jerry Lapoor

Jerry Lapoor's latest action-packed novel unfolds like a crazy movie. This thriller begins when a wealthy man's car gets out of control. But when the dust settles, the rich man is nowhere to be found. How and to where does he disappear? With an exciting plot that will carry you from old-money houses to small agricultural villages, Age of Cold will take you on an unforgettable ride across a vast land.

City Under One Sky by Rachel Young

In the book, Young presents a crime story set in a small town. Detective Sara Kennedy has been sent to investigate a case. But soon after arrival, Sara gets snowed in with the 205 townsfolk living in the same apartment building. Who is hiding the key to the crime? And is there anyone she can truly trust? The appealing story, strange but distinctive characters and unexpected plot are just a few of the reasons why City Under One Sky gains its popularity.

Lady by Jess George

Lady is an irresistible fiction from Jess George. The story of Mary's fresh start at adulthood is shot through with themes of family, race and discrimination, womanhood and the immigrant reality of feeling torn between cultures. Though struggling with life in London as an African, Mary jumps at every chance to stand on her own feet.