This Monday, the nation will start to celebrate Presidents' Day, just seven days before George Washington's birthday. Everyone agrees that day is a holiday. but is it just to celebrate George Washington's Birthday? What about Abraham Lincoln? Some government offices call it Presidents' Day. Others say the holiday is officially Washington's Birthday. Confused yet?

    George Washington was elected the country's first President on April 30,1789. Soon after, Americans began publicly celebrating his birthday. Presidential historians say the actual date of George Washington's birth is February 11,1732. But a change inthe calendar system 20 years later shifted all dates, making Washington's birthday February 22, which is now well accepted. In 1879. Congress made Washington's birthday an official federal holiday. It was the first federal holiday to celebrate an individual's birthday. In 1968, Congress passed the Monday Holidays Act, which moved the holiday to the third Monday in February. The new law did not change the holiday's name. It was still called Washington's Birthday, even though some law makers wanted to call it Presidents' Day to include Abraham Lincoln, whose actual birthday is February 12.

    Many people argue that the holiday should celebrate all past Presidents. They feel Lincoln should be honored for his role in preserving the nation during the Civil War and helping to free slaves. Others feelthe holiday should only honor Washington. the country's first President. They say shifting the focus away from Washington would mean future generations of kids would not know about the Father of Our Country.

    Laws have been introduced in Congress over the years to requireuse of the term “George Washington's Birthday.”but none of those laws have been passed. Meanwhile, many stategovernments and school districts now use the term “Presidents' Day．”Many stoles also use it to promote holiday sales.

    Should the holiday honor Washington, Washington and Lincoln, or all past Presidents? Write to emailbag@timeforkids, com and tell us what you think.

    Newborns begin to develop language skills long before they begin speaking. And, compared to adults, they develop these skills more quickly. People have a hard time learning new languages as they grow older, but babies have the ability to learn any language easily.

    For a long time, scientists have tried to explain how such young children can learn the complicated grammatical rules and sounds of a language. Now, researchers are getting a better idea of what's happening in the brains of the tiniest language learners. This new information might help kids with learning problems as well as adults who want to learn new languages. It might even help scientists who are trying to design computers that can communicate like people do.

    Most babies go “ma ma” by 6 months of age, and most children speak in full sentences by age 3. For many years, scientists have wondered how the brains of young children figure out how to communicate using language. With help from new technologies, scientists are now finding that babies begin life with the ability to learn any language. They get into contact with other people, listen to what they say and watch their movements very closely. That is why they quickly master the languages they hear most often.

    Studies show that, up to about 6 months of age, babies can recognize all the sounds that make up all the languages in the world. Starting at around 6 months old a baby's brain focuses on the most common sounds it hears. Then, children begin responding only to the sounds of the language they hear the most.

    In a similar way older babies start recognizing the patterns that make up the rules of their native language. For example, English children who are about 18 months old start to figure out that words ending in “-ing” or “-ed” are usually verbs, and that verbs are action words.

    Mark and his brother Jason both were looking at the shining new computer enviously. Jason was determined not to go against their father's wishes but Mark was more adventurous than his brother. He loves experimenting and his aim was to become a scientist like his father.

     “Dad will be really mad if he finds out you've been playing with his new computer” Jason said, “He told us not  to touch it.”

     “He won't find out,” Mark said, “I'll just have a quick look and shut it down.”

    Mark had been scolded before for touching his father's equipment. But his curiosity was difficult to control and this new computer really puzzled him.

It was a strange-looking machine — one his dad had brought home from the laboratory where he worked. “It's an experimental model,” his father had explained, so don't touch it under any circumstances.” But his father's warning only served to make Mark more curious. Without any further thought, Mark turned on the power switch. The computer burst into life and seconds later, the screen turned into colours, shifting and changing, and then two big white words appeared in the centre of the screen: “SPACE TRANSPORTER.”

     “Yes!” Mark cried excitedly, “It's a computer game. I knew it! Dad's only been pretending to work. He's really been playing games instead!” A new message appeared on the screen:

“ENTER NAMES

VOYAGE 1

VOYAGE 2

    Mark's finger flew across the keyboard as he typed in both of their names.

“INPUT ACCEPTED.

START TRANSPORT PROGRAM.

AUTO-RETRIEVE INITIATED( 自动回收程序已启动).”

    The screen turn even brighter and a noise suddenly rose in volume.

     “I think we'd better shut it off, Mark,” Jason yelled out in terror, reaching for the power switch. A beam(光束) of dazzling white light burst out of the computer screen, wrapping the boys in its glow(光芒)，until they themselves seemed to be glowing. Then it died down just as suddenly as it had burst into life. And the boys were no longer there. On the screen, the letters changed：

“TRANSPORT SUCCESSFUL．

DESTINATION:  MARS.

RETRIEVE DATE:  2025

    Feeding birds is a popular way to watch wildlife. But experts say it might put wild birds at risk.

    Feeding birds is not necessary for their survival except in extreme weather conditions. Feeders(喂食器)can definitely help birds get through that kind of weather. But most birds eat insects and show little interest in bird feeders. For those birds, we can grow native plants in a natural environment. Birds which are fond of eating seeds will be more likely to come to feeders if there is some cover nearby. This lets them feed and then fly to protective areas, such as in trees.

    The most common mistake people make with their bird feeders is that they put feeders in places where birds are easily frightened by passers-by, risk being hurt by cats, or risk flying into windows.

    So set up a bird feeder at least one meter away from a window. That way, if a bird gets frightened, it won't get killed when it hits the glass. Owners of cats should keep them inside home so they can't hurt the birds.

    Some birds are more aggressive at feeders. They eat a lot and do not leave much food for other birds. A solution is to put the food in more than one place by using different kinds of seeds or fruits. This can also increase the number and diversity of birds in your neighborhood. But don't feed wild birds anything salty, like potato chips, or food that could choke them, like bread.

    Pay attention to food quality and freshness. Unprotected food left too long in feeders will turn moldy(发霉), which can kill wildlife.

    Another word of advice: Always provide a supply of clean water for birds, but use care when looking for the right birdbath. If the birdbaths are too deep for birds, putting a few large stones in the water can give the birds a place to sit.

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.

In life, once on a path, we tend to follow it, for better or worse. What's sad is that even if it's the latter, we often accept it anyway because we are so used to the way things are that we don't even recognize that they could be different. This is a phenomenon psychologist call functional fixedness.

This classic experiment will give you an idea of how it works and a sense of whether you may have fallen into the same trap: People are given a box of tacks (大头钉) and some matches and asked to find a way to attach a candle to a wall so that it burns properly.

Typically, the subjects try tacking the candle to the wall or lighting it to fix it with melted wax. The psychologists had, of course, arranged it so that neither of these obvious approaches would work. The tacks are too short, and the paraffin (石蜡) doesn't stick to the wall. So how can you complete the task? The successful technique is to use the tack box as a candle-holder. You empty it, tack it to the wall. and stand the candle inside it. To think of that, you have to look beyond the box's usual role as a receptacle just for tacks and re-imagine it serving an entirely new purpose. That is difficult because we all suffer to one degree or another from functional fixedness.

The inability to think in new ways affects people in every corner of society. The political theorist Hannah Arendt coined the phrase" frozen thoughts" to describe deeply held ideas that we no longer question but should. In Arendt's eyes, the self- content reliance on such accepted "truths" also made people blind to ideas that didn't fit their worldview, even when there was plenty of evidence for them.

Frozen thinking has nothing to do with intelligence. She said," It can be found in highly intelligent people."