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    You may like chewing gum (口香糖) after meals to stop your breath smelling bad; or your mother might use a special neutralizer (调理剂) to protect her permed hair (烫发). But have you thought about the chemical principles behind such everyday actions?

    On March 2, the Senior 3 students from the IB (International Baccalaureate, 国际文凭) classes at Beijing Huijia Private School presented their discoveries, all in fluent English. This kind of seminar is held every year to show the achievements of the IB chemistry experiment lessons offered by the school. IB is a qualification based on a common curriculum (课程) for students aged 16-18 in any country and is recognized by universities everywhere.

    "Once I saw an advertisement for xylitol (木糖醇) gum," recalled Zhang Xinju. "Suddenly an idea came to my mind: are there any chemical reactions when the xylitol is working on our teeth?"

    Zhang and his partner Bu Xuan visited several hospitals to try and find out. "Doctors know that xylitol can protect teeth, but few could explain how the chemical reactions happen," said the 17-year-old boy.

    Presenting the results of their research in English to an audience of Chinese and foreign judges was never a problem for the students.

    "Textbooks for IB students are in English, and our teachers speak in English," explained Wei Duan and Han Yu, whose research topic was "The Acid-Base Reaction (酸碱反应) in the process of Hair-Perming".

    "In Senior 1 we often referred to Chinese textbooks, but we found we could understand and express it all in English by the second year."

    Lu Jiang, the school's IB chemistry teacher and China's only IB vice-examiner, is proud that her students can apply scientific theories they learn in class to daily life.

    "You might have learned these facts from you kindergarten teachers, but few think about the theories behind them," Lu said. "This kind of practice is intended to develop the scientific thinking they will need in their future studies."

    I was never very neat，while my roommate Kate was extremely organized. Each of her objects had its place，but mine always hid somewhere. She even labeled(贴标签) everything. I always looked for everything. Over time，Kate got neater and I got messier. She would push my dirty clothing over，and I would lay my books on her tidy desk. We both got tired of each other.

    War broke out one evening. Kate came into the room. Soon，I heard her screaming，“Take your shoes away！Why under my bed！” Deafened，I saw my shoes flying at me. I jumped to my feet and started yelling. She yelled back louder.

    The room was filled with anger. We could not have stayed together for a single minute but for a phone call. Kate answered it. From her end of the conversation，I could tell right away her grandma was seriously ill. When she hung up，she quickly crawled(爬) under her covers，sobbing. Obviously，that was something she should not go through alone. All of a sudden，a warm feeling of sympathy rose up in my heart.

    Slowly，I collected the pencils，took back the books，made my bed，cleaned the socks and swept the floor，even on her side. I got so into my work that I even didn't notice Kate had sat up. She was watching，her tears dried and her expression one of disbelief. Then，she reached out her hands to grasp mine. I looked up into her eyes. She smiled at me，“Thanks.”

    Kate and I stayed roommates for the rest of the year. We didn't always agree，but we learned the key to living together：giving in，cleaning up and holding on.

    For a long time being happy was considered something that just happened, and there was nothing special about it. Now we know that getting along with other people is something that we can work at. It is possible to act in such a way that other people will like us better. One way is being unselfish, not wanting everything from our friends. Another way is to look for good points, not bad ones in other people. It is surprising how successful this treasure hunt can be.

    You don't have to be spineless (软弱的) in order to be popular. In fact, you will be liked and respected if you are not afraid to stand up for your rights. But do it politely and pleasantly. Being friendly and polite to your group, to other people and to strangers and especially to those who do not look important or do not interest you is one way to develop a good character.

    You can not expect to be perfect, and so you must learn not to be unhappy when you make mistakes. Everyone makes mistakes, and no one is to be blamed (责备) unless he refuses to learn from them. Many young people become discouraged when they know in themselves qualities (品格) that they do not like—selfishness, laziness, and other unpleasant qualities. Just remember that we all have some of these faults and have to fight against them.

    At the same time, it is important to remember that, while you are probably no worse than others, the best way to be happy is to think yourself above other people. When something is wrong, it is good sense to try to make it right. Perhaps you don't like a teacher or a classmate. Try to see why, and look at yourself, too. To be sure that you are not doing anything to make that person dislike you. Some day, things may turn out all right, then you will have to learn to get along the best with situation, without thinking too much about it. Worrying never helps in a situation you can't change.

    Chinese scientists recently have produced two monkeys with the same gene, Zhong Zhong and Hua Hua, using the same technique that gave us Dolly the sheep. These monkeys are not actually the first primates(灵长类)to be cloned. Another one named Tetra was produced in the late 1990s by embryo(胚胎)splitting, the division of an early-stage embryo into two or four separate cells to make clones. By contrast, they were each made by replacing an egg cell nucleus(原子核)with DNA from a differentiated body cell. This Dolly method, known as somatic cell nuclear transfer(SCNT), can create more clones and allows researchers greater control over the edits they make to the DNA.

    Success came from adopting several new techniques. These included a new type of microscopy to better view the cells during handling or using several materials that encourage cell reprogramming, which hadn't been tried before on primates. Still, the research process proved difficult, and many attempts by the team failed. Just two healthy baby monkeys born from more than 60 tested mothers. This leads to many researchers' pouring water on the idea that the team's results bring scientists closer to cloning humans. They thought this work is not a stepping stone to establishing methods for obtaining live born human clones. Instead, this clearly remains a very foolish thing to attempt, it would be far too inefficient, far too unsafe, and it is also pointless.

    But the scientists involved emphasize that this is not their goal. There is now no barrier for cloning primate species, thus cloning humans is closer to reality. However, their research purpose is entirely for producing non-human primate models for human diseases; they absolutely have no intention, and society will not permit this work to be extended to humans. Despite limitations, they treat this breakthrough a novel model system for scientists studying human biology and disease.

    During an earthquake, you should know what to do. If the earthquake strikes while you're inside a house, you should lie on the floor under a strong table or other furniture. If there is no furniture, you can cover your head with your arms and keep still in the corner of the room. You should keep away from windows, glass walls, or anything that can fall.

    If you are in bed, hold firmly onto your bed and make use of a pillow to safeguard your head. You may use a doorway but only when it is close to you. It should also be considered whether it is strong enough to deal with the load.

    If you are running out, do not use lifts, even if they work. Electricity may go out at any time. Many injuries happen when people try to rush out. This means you ought to stay in your house or perhaps wherever you are.

    When you stay outdoors, you should stay far from buildings, power wires or lights. You should be in the open until the quake stops. Remember that many earthquake deaths outside the house come from falling-apart walls, flying glass and other falling things.

    If an earthquake strikes and you are driving, you should pull up to the side of the highway and stop as quickly as possible. You ought not to stop under trees, buildings or energy wires. Don't stop in the middle of the street as it could trouble others.

    When trapped, you shouldn't move. Your mouth should be covered with a piece of clothing or a handkerchief. This is because it is possible for you to breathe in some dust. Do not shout whenever possible. You should only shout in the end to get help from rescuers.

    Ender's Game

    Aliens(外星人) have attacked Earth twice and almost destroyed the human beings. We couldn't lose anymore. Therefore, the world government has started to train military geniuses(军事天才) in the arts of war. Ender Wiggin is taking part in this training. He wins all the games. He knows time is running out but can he save the planet? It is a good science fiction for boys.

    Hatchet

    It is the story of a boy named Brian. On a trip to the Canadian oilfields to spend the summer with his dad, the pilot of the Cessna he is traveling in suffers a heart attack and dies. Brian must land the plane in the forest. Brian learns to exist in the forest. He faces many dangers including hunger, animal attacks, and even a tornado.

    Ball Don't Lie

    Sticky, 17, is from the streets and has had a tough life so far. But, his hope for his life to be good and get better is basketball. His basketball skills may be his ticket to a better life. This book is inspiring, and raises questions about race and the difficulties in getting ahead in life when you've had a bad start.

    Crackback

    Miles Manning likes to please people, his father, his coach, and his friends. He is a starter on a winning football team that is favored to win the conference and have a chance to go to state. However, everybody is pressing Miles to be bigger, stronger and faster, including his new head coach, his demanding father, and his best friend.

    She

    A college professor and his young student follow instructions on a broken pottery shard (陶瓷碎片) that lead them to a fabled(传说中的) lost city in the jungles of Africa, where they encounter She Who Must Be Obeyed, the ruler of the land.