It's 5:00 in the morning when the alarm rings in my ears. I roll out of bed and walk blindly through the dark into the bathroom. I turn on the light and put on my glasses. The house is still as I walk downstairs while my husband and three kids sleep peacefully. Usually I go for a long run, but today I choose my favorite exercise DVD. Insanity. Sweat pours down my face and into my eyes. My heart races as I face my body to finish each movement. As I near the end of the exercise, I feel extremely tired, but a smile is on my face. It's not a smile because the DVD is over, but a smile of success from pushing my body to its extreme limit.

    Some people enjoy shopping, smoking, food, work, or even chocolate. But I need exercise to get through each day. Some shake heads when they see me run through the town. Others get hurt when I refuse to try just one bite of their grandmother's chocolate cake. They raise their eyebrows, surprised by my “no thank you,” or by my choice to have a salad. Over the years , I have learned it's okay to just say “no.” I shouldn't feel sorry for refusing food that I don't want to eat.

    So what drives me to roll out of bed at 5:00 a.m.? What gives me the reason to just say no to ice cream? Commitment. A commitment to change my life with a way that reduces daily anxiety, increases self –confidence and energy, extends life and above all improves my body shape. This is the point where a smile appears on my face as I look at myself in the mirror or try on my favorite pair of jeans that now fit just right. It's through commitment and sweat that I can make a difference within myself inside and out.

B

    Steven Stein likes to follow garbage trucks. His strange habit makes sense when you consider that he's an environmental scientist who studies how to reduce litter, including things that fall off garbage trucks as they drive down the road. What is even more interesting is that one of Stein's jobs is defending an industry behind the plastic shopping bags.

    Americans use more than 100 billion thin film plastic bags every year. So many end up in tree branches or along highways that a growing number of cities do not allow them at checkouts(收银台). The bags are prohibited in some 90 cities in California, including Los Angeles. Eyeing these headwinds, plastic-bag makers are hiring scientists like Stein to make the case that their products are not as bad for the planet as most people assume.

    Among the bag makers' arguments: many cities with bans still allow shoppers to purchase paper bags, which are easily recycled but require more energy to produce and transport. And while plastic bags may be ugly to look at, they represent a small percentage of all garbage on the ground today.

    The industry has also taken aim at the product that has appeared as its replacement: reusable shopping bags. The stronger a reusable bag is, the longer its life and the more plastic-bag use it cancels out. However, longer-lasting reusable bags often require more energy to make. One study found that a cotton bag must be used at least 131 times to be better for the planet than plastic.

    Environmentalists don't dispute（质疑） these points. They hope paper bags will be banned someday too and want shoppers to use the same reusable bags for years.

    We all know what a brain is. A doctor will tell you that the brain is the organ of the body in the head. It controls our body's functions, movements, emotions and thoughts. But a brain can mean so much more.

    A brain can also simply be a smart person. If a person is called brainy, he is smart and intelligent. If a family has many children but one of them is super smart, you could say, “He's the brains in the family.” And if you are the brains behind something, you are responsible for developing or organizing something. For example, Bill Gates is the brains behind Microsoft.

    Brain trust is a group of experts who give advice. Word experts say the phrase “brain trust” became popular when Franklin D. Roosevelt first ran for president in 1932. Several professors gave him advice on social and political issues（问题）facing the U.S. These professors were called his “brain trust”.

    These ways we use the word “brain” all make sense. But other ways we use the word are not so easy to understand. For example, to understand the next brain expression, you first need to know the word “drain”. As a verb, to drain means to remove something by letting it flew away. So a brain drain may sound like a disease where the brain flows out of the ears. But, brain drain is when a country's most educated people leave their countries to live in another. The brains are, sort of, draining out of the country.

    However, if people are responsible for a great idea, you could say they brainstormed it. Here, brainstorm is not an act of weather. It is a process of thinking creatively about a complex topic. For example, business leaders may use brainstorming to create new products, and government leaders may brainstorm to solve problems.

    If people are brainwashed, it does not mean their brains are nice and clean. To brainwash means to make some accept new beliefs by using repeated pressure in a forceful or tricky way. Keep in mind that brainwash is never used in a positive way.

    Living in a foreign culture can be exciting, but it can also be confusing(令人迷惑的). A group of Americans who taught English in other countries recently discussed their experiences. They found that miscommunication was always possible, even over something as simple as "yes" and "no".

    On her first day in Micronesia, an island in the Pacific, Lisa thought people weren't paying any attention to her. The day was hot. She went into a store and asked, "Do you have cold drinks？" The woman there didn't say anything. Lisa repeated the question. Still the woman said nothing. She later learned that the woman had answered her: She had raised her eyebrows(眉毛), which in Micronesia means "yes".

    Jan remembered an experience she had in Bulgaria, a country in Europe. She went to a restaurant that was famous for its cabbage. She asked the waiter, "Do you have cabbage today？" He nodded his head. Jan waited, but the cabbage never came. In that country, a nod means "no".

    Tom had a similar problem when he arrived in India. After explaining something in class, he asked his students if they understood. They answered with many different nods and shakes of the head. He thought some people had not understood, so he explained again. When he asked again, they did the same thing. He soon found out that his students did understand. In India, people nod and shake their heads in different ways depending on where they come from. You have to know where a person is from to understand whether they mean "yes" or "no"．

    Ever walked to the shops only to find, once there, you've completely forgotten what you went for? Or struggled to remember the name of an old friend? For years we've accepted that a forgetful brain is as much a part of aging as wrinkles and gray hair. But now a new book suggests that we've got it all wrong.

    According to The Secret Life of the Grown-up Brain, by science writer Barbara Strauch, when it comes to the important things, our brains actually get better with age. In fact, she argues that some studies have found that our brain hits its peak between our 40s and 60s — much later than previously thought.

    Furthermore, rather than losing many brain cells as we age, we keep them, and even produce new ones well into middle age. For years it's been assumed that brain, much like the body, declines with age. But the longest, largest study into what happens to people as they age suggests otherwise.

    This continuing research has followed 6,000 people since 1956, testing them every seven years. It has found that on average, participants performed better on cognitive (认知的) tests in their 40s and 50s than they had done in their 20s. Specifically, older people did better on tests of vocabulary, verbal memory (how many words you can remember) and problem solving. Where they performed less well was number ability and perceptual speed — how fast you can push a button when ordered. However, with more complex tasks such as problem-solving and language, we are at our best at middle age and beyond. In short, researchers are now coming up with scientific proof that we do get wiser with age.

    Neuroscientists are also finding that we are happier with aging. A recent US study found older people were much better at controlling and balancing their emotions. It is thought that when we're younger we need to focus more on the negative aspects of life in order to learn about the possible dangers in the world, but as we get older we've learned our lessons and are aware that we have less time left in life: therefore, it becomes more important for us to be happy.

Scientists have long thought about whether each animal species has a different language, much like different human languages that we cannot understand. Language experts agree on the fact that the way animals communicate through various calls does not fit the definition of human languages.

Animal calls are not considered a language because the calls are limited to signals related to food activities, warning about the presence of enemies and so on. They lack the characteristic of productivity that all human languages share. That is — humans create new expressions every day by combining different words to express meanings. Animal calls are fixed in their meanings, while human language goes further and includes expressions of complex ideas that do not have a limit.

However, animals do communicate. People who study humans believe that people speak with their entire bodies. To express a message, one does not always need words. Have you ever shared a private joke with your friends across the table? All you did was to give them a self-satisfied smile, Animals can communicate in much the same way as humans do. Although animals do not have the ability to speak words, they can use other methods, such as gestures, movements, calls and their sense of smell. In short, most of their communication is not related with speech.

If animals can make noises, why can't they talk? Humans and animals both have the necessary organs that produce sounds, such as lungs, throat, voice box, lips and tongue. But the differences lie in the movement and relative position of these organs that make it possible for us to speak.

When humans developed from apes, a lot of our features were improved to better shape sounds along the way. The mouth started getting smaller and the neck grew longer. All other animals, including our closest animal relatives — chimpanzees, have little similarity, which determines humans' ability to speak.