注意：1）词数100字左右。

2）可适当增加细节，以使行文连贯。

3）参考词汇：物件item

4）文章开头已给出。

    Facing the four items put forward by my psychology teacher, I, a Senior Three student, ……

The Possible Health Dangers of Air-conditioners

Although many of us may feel air-conditioners bring relief from hot, humid or polluted outside air, they pose many potential health hazards. Much research has looked at how the movement of air inside a closed environment—such as an office building—can spread disease or expose people in the building to harmful chemicals.

    One of the more widely publicized dangers is that of Legionnaire's disease, which was first recognized in the 1970s. This was found to have affected people in buildings with air-conditioning systems in which warm air pumped out of the system' cooling towers was somehow sucked back into the air intake, in most cases due to poor design. The warm air, filled with bacteria, was combined with cooled, conditioned air and was then circulated around various parts of the building. Studies showed that even people outside such buildings were at risk if they walked past air exhaust pipes.

    Large air-conditioning systems add water to the air they circulate by means of humidifiers. In older systems, the water used for this process is kept in special reservoirs, the bottoms of which provide breeding grounds for bacteria which can find their way into the ventilation system. The risk to human health from this situation has been highlighted by the fact that the immune systems of approximately half of workers in air-conditioned office buildings have developed the ability to fight off the organisms found at the bottom of system reservoirs. But chemicals called “biocides” are added to reservoirs to make them germ-free, and they are dangerous in their own right in sufficient quantities, as they often contain compounds strongly linked to cancers.

    Finally, it should be pointed out that the artificial climatic environment created by air-conditioners can also affect us. In a natural environment, whether indoor or outdoor, there are small variations in temperature and humidity. Indeed, the human body has long been accustomed to these normal changes. In an air-conditioned living or working environment, however, body temperatures remain well under 37℃, our normal temperature. This leads to a weakened immune system and thus greater exposure to diseases such as colds and flu.

    Although being famous might sound like a dream come taste, today's stars, feeling like zoo animals, face pressures that few of us can imagine. They are at the center of much of the world's attention. Paparazzi(狗仔队)camp outside their homes, cameras ready. Tabloids(小报)publish thrilling stories about their personal lives. Just imagine not being able to do anything without being photographed or interrupted for a signature.

    According to the psychologists, celebrities(名人)worry constantly about their public appearance. Eventually, they start to lose track of who they really are, seeing themselves the way their fans imagine them, not as the people they were before everyone knew their names. Over little, they feel separated and alone.

    The phenomenon of tracking celebrities has been around for ages. In the 4th century B C., painters followed Alexander the Great into battle, hoping to picture his victories for his admirers. When Charles Dickens visited America in the 19th century, his sold-out readings attracted thousands of fans, leading him to complain about his lack of privacy. Tabloids of the 1920s and 1930s ran articles ghoul filth-slats in much the same way that modern tabloids and websites do.

    Being a public figure today, however, is a lot more difficult than it used to be. Superstars cannot move about without worrying about photographers with modem cameras. When they say something silly or do something ridiculous, there is always the Internet to spread the news in minutes and keep their "story" alive forever.

    If fame is so troublesome. Why aren't all celebrities running away from it'? The answer is there are still ways to deal with it. Some stars stay calm by surrounding themselves with trusted friends and family or by escaping to remote places away from big cities. They focus not on how famous they are but on what they love to do or whatever made theme famous in the first place. With these effective approaches, some celebrities relieve the stress and remain popular with fans. Consequently, though being famous is driving some stars crazy, some wise ones enjoy what reputation brings them.

Teens' Sleep Shortage

    Most teens need about 8 to more than 9 hours of sleep each night. The right amount of sleep is essential for anyone who wants to do well in tests or sports. And lack of sleep affects everything from a person's ability to pay attention in class to his or her mood. It also damages teens' ability to do their best in athletics. Unfortunately, research shows that many teens don't get enough sleep, and more than 20% of high school students fall asleep in class.

    Until recently, teens were often blamed for staying up late, oversleeping for school, and falling asleep in class. But recent studies show that teens' sleep patterns actually differ from those of adults or kids. These studies show that during the teen years, the body's biological clock is temporarily reset, telling a person to fall asleep later and wake up later. This change might arise from the fact that the brain hormone melatonin (褪黑素) is produced later at night for teens than it is for kids and adults. This can make it harder for teens to fall asleep early.

    These changes in the body's biological clock are in line with a time when they're busier than ever. For most teens, the pressure to do well in school is heavier than when they were kids, and it's harder to get by without studying hard. And teens also have other time demands — everything from sports and other extracurricular(课程外的) activities to fitting in a part-time job to save money for college.

    Early start time in some schools may also play a role in this sleep shortage. Teens who fall asleep after midnight may still have to get up early for school, meaning that they may only squeeze in 6 or 7 hours of sleep a night. A couple hours of missed sleep a night may not seem like a big deal, but can create a noticeable sleep shortage over time

    Tired of all the pushing in supermarkets? Fed up with waiting in endless lines to pay for what you have bought? Angry at wasting time in traffic jams only to find no parking spaces when you eventually arrive at the store? If this is you, then online shopping is the answer to your dreams of trouble-free shopping, or is it?

    Online shopping brings its own challenges. Here are a few things to bear in mind when browsing (浏览) various websites. The claim (声明) made by online sites is that shopping online is a safe and secure way to make purchases. The evidence challenges this. In any case, you only have to be the victim of fraud (欺骗) once to experience all the problems that come with this form of deceiving. Use only sites that have a trusted history and an excellent reputation.

    Another problem is that the appearance of items in reality is often quite different from what you see on your computer screen. This might not be a problem if you are buying washing powder but could be a major disappointment when that beautiful blue dress you ordered turns up in green. Also, product descriptions are sometimes simply untrue! Perhaps the wisest plan is to purchase items where design and colour are not essential to customer satisfaction.

    Some even argue that online shopping indirectly contributes to global warming. Yes, your car can stay parked but how are online goods delivered? Often by some large vans pouring out carbon monoxide(一氧化碳) and adding to our already desperate traffic problems. You are also by now becoming increasingly irritated(烦恼的) by the fact that the delivery is late and you have wasted the leave from work to receive it!

Whatever happened to the fight of carbon capture?

Debates have been going on around the subject of carbon capture. Scientists, especially engineers and geologists, have strongly criticized green groups who claimed that carbon capture and storage (CCS) schemes are costly mistakes.

The scientists insisted that such schemes are vital weapons in the battle against global heating. They also wan that failure to set up ways to trap and store carbon would make it impossible to meet the emissions target by 2050." CCS is going to be the only effective way in the short term to prevent our steel industry, cement manufacture and many other processes from continuing to pour emissions into the atmosphere," said Professor Stuart Haszeldine, of Edinburgh University. "If we are to have any hope of keeping global temperature increases down below 2 degrees Celsius, we desperately need to develop ways to capture and store carbon dioxide."

Green groups claimed CCS would not make "a meaningful contribution to 2050 climate targets". They say CCS was not a reliable way to decarbonize the energy system and that CCS has a "history of over-promising and under-delivering". Instead, they urged the construction of more renewable energy plants to be given priority.

But the claims were dismissed by engineers and geologists, "These claims are quite unfair" said Michael Stephenson, director at the British Geological Survey. "The technology behind carbon capture and storage is fully mature. It offers us a genuine solution to some of the problems we face in trying to deal with global warming."

A government spokesman for the Department of Energy and Climate Change said, "We are committed to meeting our climate change targets in a way that is affordable and provides secure energy to families and businesses. We are considering the role that CCS could play in decarbonization of the UK. But we also need to take government spending into account. CCS had better come down in cost."