Can people change their skin color without suffering like pop king Michael Jackson? Perhaps yes. Scientists have found the gene that determines skin color.

    The gene comes in two versions, one of which is found in 99 percent of Europeans. The other is found in 93 to 100 percent of Africans, researchers at Pennsylvania State University report in the latest issue of Science.

    Scientists have changed the color of a dark-striped zebra-fish（斑马鱼） to uniform gold by inserting a version of the pigment (色素) gene into a young fish. As with humans, zebra-fish skin color is determined by pigment cells, which contain melanin (黑色素). The number, size and darkness of melanin per pigment cell determine skin color.

    It appears that, like the golden zebra-fish, light-skinned Europeans also have a mutation (变异) in the gene for melanin production. This results in less pigmented skin.

    However, Keith Cheng, leader of the research team, points out that the mutation is different in human and zebra-fish genes.

    Humans acquired dark skin in Africa about 1.5 million years ago to protect bodies from ultra-violet rays of the sun (太阳光紫外线), which can cause skin cancer.

    But when modern humans leave Africa to live in northern latitudes, they need more sunlight on their skin to produce vitamin D. So the related gene changes, according to Cheng.

    Asians have the same version of the gene as Africans, so they probably acquired their light skin through the action of some other gene that affects skin color, said Cheng.

    The new discovery could lead to medical treatments for skin cancer. It also could lead to research into ways to change skin color without damaging it like chemical treatment did on Michael Jackson.

                                                                              Learning a Second Language

    Some people learn a second language easily. Others have trouble learning a new language. How can you help yourself learn a new language, such as English? There are several ways to make learning English a little easier and more interesting.

    The first step is to feel positive about learning English. If you believe that you can learn, you will learn. Be patient. You do not have to understand everything all at once. It is natural to make mistakes when you learn something new. We can learn from our mistakes. In other words, do not worry about taking risks.

    The second step is to practice your English. For example, write a diary every day. You will get used to writing it in English, and you will feel comfortable expressing your ideas in English. Several weeks later, you will see that your writing is improving. In addition, you must speak English every day. You can practice with your classmates outside class. You will all make mistakes, but gradually you will become comfortable communicating in English.

    The third step is to keep a record of your language learning. You can write this in your journal. After each class, think about what you did. Did you answer a question correctly? Did you understand something the teacher explained? Perhaps the lesson was difficult, but you tried to understand it.

    You must be positive about learning English and believe that you can do it. It is important to practice every day and make a record of your achievements. You will enjoy learning English, and you will feel more confident in yourself.

    Variety is the spice of language. The words listed in this book are not intended to replace those that most people use most of the time. Rather, they are variations on the theme. We tend to use the same old words over and over again, to limit our powers of expression by limiting our vocabulary. {#blank#}1{#/blank#} but why not enhance your speech and writing by learning to use new ones from time to time ds alternatives?

    How often have you spoken of having an accident? {#blank#}2{#/blank#} Or why not occasionally describe a situation as aggravated（恶化）instead of worsened.

    I don't mean that you should throw away the Mold words”. {#blank#}3{#/blank#} English is an especially rich language, and often there are differences between two words that are generally regarded as die same. Thus, a mishap is not merely an accident; it is an unfortunate accident. Because there can be fortunate accidents, like bumping into an old friend you haven't seen for years and whose address you've lost. {#blank#}4{#/blank#}.

    No doubt a good many words in the list will be familiar to you, but do you use them, or do they remain the “property” of others? {#blank#}5{#/blank#}Try to make these words your own, as companions or friendly rivals of the ones you have owned in the past. Let them compete, and make your language all the richer.

A. Just vary them with the “new words”.

B. Many words have more than one meaning.

C. There is nothing wrong with the “old words”.

D. English words are grouped according to their origins.

E. Why not use the alternative mishap once in a while?

F. They are included to introduce variety into your speech and writing.

G. So in using mishap instead of accident, you must be sure of the difference.

    To see the world is one thing; to have someone to share it with is another. Indeed, travel becomes more interesting when you have a travel partner. A travel partner can be a close friend, a family member, a pal you've met online, or a business friend.

    You can have someone to talk to.

    Traveling alone is fun, but wouldn't you feel lonely？Having a travel partner can remove the feeling of loneliness. This is especially true if you can get a travel companion who is very familiar with the place you're traveling to. You don't have to ask any information from the locals, and you can increase the time you spend in the country.

    __________________________

    One of the major headaches in traveling is the costs involved. You can't simply ignore the rising price of hotels or plane tickets. You should also think about your daily needs, such as your food. Of course, you can't simply go back without bringing any souvenirs (纪念品) to your friends and family. All these can ruin your budget. However, when you have a travel friend, you can have someone to share the expenses with.

    You can meet a good friend.

    Having a travel mate is a good way of meeting a new friend or even a lifelong partner. You can never count the number of couples who actually found their way into each other's heart while traveling together in another country.

    You can have someone to watch out for you.

    When you're in a foreign land, you'll never be really safe. You don't know the rules as well as the culture of the people. A travel mate will be perfect to remind you of your duties in the country and to watch your back just in case you get lost.So why don't you find a travel companion now?

    Let's find out how...

    Why we cry with happiness show: Responding with a negative reaction helps us deal with extreme joy. If you cry with happiness at weddings, you are responding to a happy experience with a negative reaction. The researchers believe the unusual reaction may help renew emotional balance in us and keep extreme emotions under control. The findings make it clear how people express and control their emotions, which could help improve their understanding of people's mental(精神的) health.

    Dr Oriana Aragon set out to explore the phrase “tears of joy”, which she said never made sense to her. But after studying a series of incongruous(不和谐的) expressions, she now understands better why people cry when they are happy. “People may be renewing emotional balance with these expressions,” she explained. “They seem to take place when people are struck by strong positive emotions. People, who do this, seem to recover better from those strong emotions.”

    The report show various examples of responding to a positive experience with a negative emotion, such as, a crying wife seeing the husband returning from war again, and teenage girls screaming at a Justin Bieber concert. Examples also include a baseball player who hits a home run, only to be slapped(拍) on the back by teammates, as well as when people cannot help kissing babies' faces who they consider lovely.

    Dr Aragon and her team discovered that people, who expressed negative reactions to positive news, were able to moderate(缓和) strong emotions more quickly. There is also some evidence that strong negative feelings may provoke positive expressions. For example, nervous laughter often happens when people are faced with a hard situation. We've seen people smiling during times of extreme sadness.

    “The findings affect our knowledge of how people express and control their emotions, which is importantly related to mental and physical health, the quality of relationships with others, and even how well people work together,” Dr Aragon said.

    Every day can be a fresh, new beginning—this is very important if you had a difficult day before. By starting with some preparations, you can face the problems of the day in a good mood(心情). {#blank#}1{#/blank#}

    Exercise. Exercising is one of the best methods to start your day for your mind as well as the body. {#blank#}2{#/blank#} In addition, it also reduces stress and improves your metabolism(新陈代谢). So go for a walk, go for a bike ride, or go to the gym in the morning.

    Organize yourself. {#blank#}3{#/blank#}Make a to-do list and try to follow it. It will keep you organized(有条理的) and make your day easier. However, make sure that your to-do list is manageable. There are only so many things you can do in a day.

    Smile. Starting your day by acting the way you want to feel can help you be in a good mood.{#blank#}4{#/blank#}The easiest thing to do is smile. Just smile because you are alive and you can. Watch or listen to something humorous so you can laugh. It makes you feel positive and really good about yourself and the world that surrounds you.

    Keep important items in the same place. To make mornings less busy, start a habit keeping your important items in a place easy to reach.{#blank#}5{#/blank#}This way, you are never looking for that lost item when you are running behind.

A. Write down the tasks for the day.

B. Try other actions to get yourself to feel happier.

C. Try some of the following tips to start your day right.

D. Put your keys, wallet, purse, and other important items there.

E. Instead of rushing through the rooming, go slow and take your time.

F. It increases brain's working speed, which can help you get a jump-start on the day.
G. If you feel angry or tired, do something physical to make yourself feel happy.