Scientists in Britain and the United States have made a new kind of enzyme(酵素) that eats plastics(塑料). With its help, plastics can be turned into smaller parts and go away quickly.

    Scientists believe that, in the future, it could solve the problem of plastic pollution.

    The enzyme is able to break down PET, a form of plastic. PET was first made in the 1940s and is now widely used to make plastic bottles. It can remain in the environment for many years and pollute large areas of land and water. So it has always been a headache to deal with the waste from PET and other plastics.

    The researchers made the discovery(发 现) while examining the structure of a natural enzyme in Japan. They found that the natural enzyme was helping to break down PET plastics. So, they

decided to make small changes to the enzyme by adding some amino acids(氨基酸). It made the natural enzyme's plastic-eating abilities work faster and better.

    John McGeehan, one of the lead researchers, said, "We've made an improved enzyme. It's better than the naturl one. And we are trying to make more improvements to it." He went on."

    The enzyme is not harmful to humans or animals, and it is friendly to the environment. So we are considering putting it into wider use."

    The team is now trying to make the enzyme break down PET in large quantities(大量的). "We'll see that the plastic pollution may be stopped with this technology. However, there is still a long way to go," John McGeehan added.

Doing housework is a key part of family life. It helps improve the relationship among family members. However, lots of Chinese parents are unaware of the importance of doing housework and they think it is a waste of time.

In order to know how often middle school students do housework at home, we did a survey among 1,200 students from Grade 7 to Grade 9 in a middle school. The following bar chart shows the result of our survey.

From the bar chart, we find that only a small number of students usually do housework. Nearly half of the students in Grade 9 never do housework. The result makes us worried.

After all, doing housework is good for students. It can teach students many important skills, like planning, timing, solving problems and so on. Doing housework can also teach students what responsibility is. Everyone should do something for the family. What's more, doing housework can help students relax themselves and keep a balance between study and life.

Therefore, we suggest that parents should encourage their children to do housework. They must learn one or two life skills every year so that they can be better prepared for an independent life in the future.

Do you want to improve your learning skills? Do you want higher marks? Do you have an important exam soon?

As we all know, environmental pollution is still serious nowadays. Our group wanted to know how many students knew about each kind of the pollution and we wanted to learn how often they sorted(分类) rubbish. So we did a survey among the students in our school. Here are the results of our questionnaire(问卷).

The results of the questionnaire

①China is one of the first countries to develop a medical culture. Compared with Western methods, traditional Chinese medicine(TCM) uses quite a different way. For thousands of years, Chinese people have got rich experience in fighting all kinds of diseases and formed a unique medical theory(理论).

②The key point behind TCM is that the human body's life is the result of the balance between yin and yang. Yang works to protect us against outer(外面的) harm, while yin is the inner base to store and provide energy. When the balance between the two is broken, people fall ill.

③One of the traditional skills of TCM, acupuncture (针刺疗法), means putting needles into superficial structures of the body - usually at acupoints(穴位) to restore the yin-yang balance. It is often together with moxibustion(灸法), which includes burning the mugwort(艾草) on or near the skin at an acupoint.

④The first known text that clearly talks about something like acupuncture and moxibustion as it is practiced today is Yellow Emperor's Inner Canon. It is the earliest and most important written work of TCM and is considered the most representative medical text in China.

⑤Acupuncture and moxibustion have caused the interest of international medical science circles. And TCM is getting worldwide popular little by little. The WTO sent a document in 2002 and called more than180 countries to use TCM as an alternative(可供选择) in their medical policies.

⑥In 2010, acupuncture and moxibustion of traditional Chinese medicine were added to the Representative List of the Intangible Cultural Heritage of Humanity by the UNESCO.