4 . Being a teenager can be challenging, but it can also be exciting. You’re becoming more independent and making decision s for yourself. You are also learning to take risks and solve problems better. And changes are happening throughout your body, even in your brain.

The changes in your brain are influencing how you develop into an adult. Imagine the structure of your brain is like a big road map. Lots of roads lead to different destinations. When you were a child, as you learnt new things, your brain created more and more roads to different destinations. By the time you become a teenager, many different roads lead to the most important places on the map. Now your brain’s job is to make that map more efficient.

As a result, your experiences as a teenager actually influence the way that your brain develops. If you spend hours playing video games, what skills do you use? You learn to see something with your eyes and respond to it with your hands. As you develop those skills, your brain is making sure that the roads leading to them are especially fast and efficient. So, your video-game playing could be preparing you for a career such as a pilot.

This is a great time for you to practice new skills and discover what you’re good at and try what you love doing. Go out and try different activities, and stick to them if you think they are useful. Remember that with everything you do, you’re shaping your brain for the future.

6 . Have you ever noticed that some people can eat what they want and stay in shape, while others carefully watch what they eat and still put on weight? How frustrating! However, scientists are beginning to believe that some people get the ability to stay thin from their parents.

Scientists say that when some people eat, their bodies will naturally store the excess energy from food as fat. These people gain weight if they eat more than they need each day. Meanwhile, other people eat more than they need but their bodies are able to “burn off” the extra food without making fat.

To show that this is true, scientists have experimented on laboratory mice. They gave the mice a special diet with a lot of fat. Some mice gained weight while the other mice stayed thin even though both groups of mice ate the same amount of food and got the same amount of exercise. Scientists concluded that weight gain seemed to be influenced by genetic factors. They also believe they have now identified the genes that may cause this tendency. These genes, according to the scientists, get passed down the generations. Armed with this knowledge, they believe it may be possible to develop medicines that can target the genes and stop people from gaining weight.

The study of weight gain is becoming more important as the number of people who are overweight continues to grow. In the United States over seventy percent of the population have weight problems. This means they are at risk of illnesses such as high blood pressure and heart disease.

Current medicines for weight control do not work very well because they can have serious side effects, such as heart problems. However it takes a long time to develop and thoroughly test new drugs.

7 . There are purple clothes, purple handbags, purple bicycles, purple furniture, even purple computers! So purple is one of the most ______ colors today. But in the past, purple was a very expensive and unusual color. Let’s take a look at the rich ______ of the color purple.

Some scientists believe that the first plants to appear on Earth over 500 million years ago _____ looked purple, not green. Plants today are green because ______ use green chlorophyll (叶绿素) to produce energy. ______ these early plants probably used something called retinal, which is a dark purple color.

During the time of the Roman Empire (37 BC-476 AD), it was very ______ to make purple dye (染料). The dye came from sea snails (海螺). But 10,000 dead sea snails ______ you just one gram of purple dye... as well as a very bad smell! This ______ purple dye was called Tyrian purple, and it was the preferred ______ of emperors.

In 16th century England, purple was ______ for the kings family members. Queen Elizabeth I’s clothes were purple, but ordinary people were not allowed to ______ the color.

In 1856, William Perkin, an 18-year-old ______ student, noticed something strange while doing an experiment. The chemicals he used to clean his instruments ______ with the chemicals he used in his experiment and produced a bright purple color. This ______ led Perkin to start a company using this chemical mixture to make purple dye. The dye was much ______ than sea snail dye. Thanks to Perkin, now anyone can afford to wear purple clothes.

8 . Knowing the cultural differences can help you understand friends who are of a different race or culture, which is beneficial to you. With this understanding, you won’t run the risk of being disrespectful. You’ll also know if you are misunderstanding your friend’s behaviour. The major differences between Asian and American teenagers lie in the following aspects.

Family

Family comes first in the Asian culture. Teenagers stay close to home and have a stronger commitment to their parents than many American teens do. While Asian families have a greater dependence on each other, American families encourage their children and teenagers to be independent.

Friendship

Some Asian teens generally prefer having a small group of life-long friends. They are committed and loyal to their friends. Americans often prefer a larger group of friends. There might be less commitment to keeping friends for life because of their bigger pool of possible friendships.

Working Relationships

If you are working on a group project with teens from China or other Asian countries, they might focus on developing a good relationship with you. However, American teens tend to first focus on the task and getting the work done. Developing relationships with their group members might come second

Body Language

In China and many other Asian countries, making direct eye contact is considered rude and disrespectful. However, in America and some European countries, it is not only seen as appropriate but also necessary because it means the person is paying attention. In Asian culture people are usually more comfortable with less personal space than Americans are.

10 . Does every dinner with your parents seem to turn into a battle? Have your once warm and open conversations become cold and guarded? Do you feel that you just cannot see eye to eye with them on anything?     1    . Heated arguments and cold silences are common between teenagers and their parents.

    2    . You may feel anxious that you are developing at a different rate to your friends, shooting up in height or getting left far behind. You might worry about your changing voice, weight problems or spots. When it all gets too much your parents are often the first targets of your anger.

It can be a big headache to balance your developing mental needs too. You enter a strange middle place,     3    . You have both a new desire for independence and a continued need for your parents’ love and support. You feel ready to be more responsible and make decisions on your own. Unfortunately, your parents do not always agree and that makes you feel unhappy. On the other hand, when you are struggling to control your feelings, you wish they could be more caring and patient. Sometimes they forget that growing up is a rough ride. It can be difficult when your parents treat you like a child but expect you to act like an adult.     4    .

Although sometimes it may seem impossible to get along with a family, you can take action to improve the situation.     5    . When you disagree with your parents, take a minute to understand the situation from their point of view and try to have a talk with them. Perhaps they have experienced something similar and do not want you to go through the same pain. After you have thought it through, explain your actions and feelings calmly, listen carefully, and address their concerns. Through this kind of healthy discussion, you will learn when to back down and when to ask your parents to relax their control.