How many chemicals does tobacco contains？

How will the present-day science develop in the near future, i.e. the next decade or so？

To【36】with, we can expect【37】science to produce a vast increase in entirely new products of all【38】.These will range from light-weight, high-strength materials for【39】in the many specialized branches of engineering,【40】drugs and chemicals with a greatly-increased selectivity 【41】can be used in medicine and agriculture. However, in this【42】case in particular, it may be predicted【43】the wide-spread application and combination of new and more complex products will give【44】to unexpected inter-reactions or side-effects. For this reason, greatly intensified programs of research will be required in【45】to discover and eliminate the harmful results of such combination.

(36)

A．talk

B．begin

C．introduce

D．research

How to Get Preserved as a Fossil

56. Unfortunately the changes of any animal become a fossil are not very great, and 57. the chances of a fossil then being discovered many thousand of years later are even less. 58. It is not surprising that all the millions of animals that have lived in the past. 59. we actually have fossils of only very few.

60. There are several ways into which animals and plants may' become fossilized. 61. First, it is essential that the remains are buried, as though dead animals and plants are quickly destroyed 62. if they remain exposed the air. Plants rot, while insects and hyenas cat the flesh and bones of animals. 63. Finally, the few remaining bones soon disintegrate the hot sun and pouring rain. If buried in suitable conditions, however, animal and plant remains will be preserved. 64. The same chemicals change sand and silt into hard rock will also enter the animal and plant remains and make them hard too. 65. When this happens, we say that they become fossilized.

(56)

Section D

Everyone knows about pollution in the environment, Water, air, and land are all polluted. This means that pollution is everywhere. Now, scientists are looking inside out bodies to find out about internal pollution.

In 2003, the Environmental Working Group studied nine people to measure the chemicals in their bodies. These nine people had an average of 53 cancer-causing chemicals in their bodies. They also had an average of 62 chemicals that can damage the brain, and 55 that can harm babies in pregnant women. Even though a lot of chemicals were found in human bodies, the chemicals were found in small amounts. The amounts were small enough that they were probably not hurting the people. However, scientists are worried because most of these chemicals were created by humans. Most of these chemicals did not exist 75 years ago. This proves that we have not only polluted the world-we have polluted our own bodies!

How dose this pollution get into our bodies？ We come into contact with many chemicals every day. For example, everyone uses soap, skin lotion, and shampoo. However, few people know that these products contain harmful chemicals, some of which may cause memory loss. Chemicals known as DEA (diethanolamine) and TEA (triethanolamine) may seep into the skin and stop us from absorbing a helpful nutrient called "choline". Choline is a nutrient that plays a crucial role in the memory cell making process in the developing brain. Some people worry that every time we wash our hair, we are decreasing our memories.

Everyone knows they should brush their teeth regularly, but recent research has show that some toothpastes can cause cancer. Fluoride is a key ingredient in many toothpastes. However, studies show that fluoride dose not really protect our teeth. In fact, fluoride has been connected with bone cancer and other diseases. While we are trying to save our smiles, we could be damaging our health.

Women are probably exposed to more chemicals than men because they use more beauty products. Recently, harmful chemicals have been found in nail polish, hair spray, deodorant, and perfume. The chemicals are called " phthalates". Studies on animals have shown that phthalates can damage the liver, the kidneys, and the lungs, Cosmetic companies say the amounts of phthalates in their products are safe, but consumer protection groups disagree. They say some women use so many products that the levels are actually high. So, the more women try to look beautiful, the more they could be harming their health.

In a futuristic story by Ray Bradbury, a man found a pristine stream on a new planet. When he drank from the stream, he died! Why？ His body was so polluted that pure water was a poison to him! Perhaps that is only science fiction, but it reminds us to take care of our bodies. We must find ways to reduce the pollution we absorb.

Summary:

Like our polluted environment, out bodies are no longer pollution-free. Scientists now know that there is pollution in our bodies. On【61】______, we have 53 cancer-causing chemicals in our bodies. Even fluoride【62】______ with bone cancer and other diseases. Some common cosmetics contain small amounts of chemicals, which seep into our【63】______ when we use these products. They prevent us from absorbing the【64】______our bodies need. So, it is【65】______that we find ways to reduce the amount of chemicals in our bodies. We should remind our friends and families to take care of their bodies.

(76)

How to Get Preserved as a Fossil

【S1】 Unfortunately the changes of any animal become a fossil are not very great, and 【S2】 the chances of a fossil then being discovered many thousand of years later are even less. 【S3】It is not surprising that all the millions of animals that have lived in the past. 【S4】we actually have fossils of only very few.

【S5】There are several ways into Which animals and plants may become fossilized.【S6】First, it is essential that the remains are buried, as though dead animals and planks are quickly destroyed 【S7】 if they remain exposed the air. Plants rot, while insects and hyenas eat the flesh and bones of animals. 【S8】Finally, the few remaining bones soon disintegrate the hot sun and pouring rain. If buried in suitable conditions, however, animal and plant remains will be preserved. 【S9】The same chemicals change sand and silt into hard rock will also enter the animal and plant remains and make them hard too. 【S10】When this happens, we say that they become fossilized.

【S1】

READING PASSAGE 1

You should spend about 20 minutes on Questions 1-13 which are based on Reading Passage 1 below.

Indoor Pollution

Since the early eighties we have been only too aware of the devastating effects of large-scale environmental pollution. Such pollution is generally the result of poor government planning in many developing nations or the short-sighted, selfish policies of the already industrialised countries which encourage a minority of the world's population to squander the majority of its natural resources.

While events such as the deforestation of the Amazon jungle or the nuclear disaster in Chernobyl continue to receive high media exposure, as do acts of environmental sabotage, it must be remembered that not all pollution is on this grand scale. A large proportion of the world's pollution has its source much closer to home. The recent spillage of crude oil from an oil tanker accidentally discharging its cargo straight into Sydney Harbour not only caused serious damage to the harbour foreshores but also created severely toxic fumes which hung over the suburbs for days and left the angry residents wondering how such a disaster could have been allowed to happen.

Avoiding pollution can be a fulltime job. Try not to inhale traffic fumes; keep away from chemical plants and building-sites; wear a mask when cycling. It is enough to make you want to stay at home. But that, according to a growing body of scientific evidence, would also be a bad idea. Research shows that levels of pollutants such as hazardous gases, particulate matter and other chemical 'nasties' are usually higher indoors than out, even in the most polluted cities. Since the average American spends 18 hours indoors for every hour outside, it looks as though many environmentalists may be attacking the wrong target.

The latest study, conducted by two environmental engineers, Richard Corsi and Cynthia Howard-Reed, of the University of Texas in Austin, and published in Environmental Science and Technology, suggests that it is the process of keeping clean that may be making indoor pollution worse. The researchers found that baths, showers,dishwashers and washing machines can all be significant sources of indoor pollution, because they extract trace amounts of chemicals from the water that they use and transfer them to the air.

Nearly all public water supplies contain very low concentrations of toxic chemicals, most ofthem left over from the otherwise beneficial process of chlorination. Dr. Corsi wondered whether they stay there when water is used, or whether they end up in the air that people breathe. The team conducted a series of experiments in which known quantities of five such chemicals were mixed with water and passed through a dishwasher, a washing machine, a shower head inside a shower stall or a tap in a bath, all inside a specially designed chamber. The levels of chemicals in the effluent water and in the air extracted from the chamber were then measured to see how much of each chemical had been transferred from the water into the air.

The degree to which the most volatile elements could be removed from the water, a process known as chemical stripping, depended on a wide range of factors, including the volatility of the chemical, the temperature of the water and the surface area available for transfer. Dishwashers were found to be particularly effective: the high-temperature spray,splashing against the crockery and cutlery, results in a nasty plume of toxic chemicals that escapes when the door is opened at the end of the cycle.

In fact, in many cases, the degree of exposure to toxic chemicals in tap water by inhalation is comparable to the exposure that would result from drinking the stuff. This is significant because many people are so concerned about water-borne pollutants that they drink o

A．has increased since the eighties.

B．is at its worst in industrialised countries.

C．results from poor relations between nations.

D．is caused by human self-interest.

We all have to learn how to stop wasting our limited water. One of the steps we should take is to find ways of reusing it. Experiments have already been done in this field.

Today in most large cities, fresh water is used only once, then it runs into waste system. But it is possible to pipe the used water to a purifying factory. There it can be filtered and treated with chemicals so that it can be used again, just as it were fresh from a spring.

But even if every large city purified and reused its water, we still would not have enough. Then we could turn to the oceans. All we’d have to do to make use of the seawater on earth is to get rid of the salt.

This process is called desalinization, and it is already in use in many parts of the world.

The way to stop wasting our limited water is to （）.

A.do experiments with water

B.purify the used water and reuse it

C.use fresh water once again

D.make use of seawater

听力原文： Tears keep your eyes wet and they also contain substance that kills certain bacteria so it can't infect your eyes. Give up your tears and you lose this on-the-spot defense. Another thing you couldn't do without your tears is cry from joy, anger or sadness. Humans are the only animals that produce tears hi response to emotions. And most people say a good cry makes them feel better. That has led many scientists to believe that crying is an adaptive response to stress, that it somehow helps us cope with emotional situations. Tear researcher William Frey is trying to find out how it happens.

"One possibility," be says, "is that tears discharge certain chemicals from your body, chemicals that build up during stress. When people talk about crying it out, I think that might actually be what they are doing." He says. If Frey is right, how do you think not crying affects those who tend to "hold it in"？ Boys, for example, cry only about a quarter as often as girls once they reach their teenage years. And we all cry a lot less now than we did as babies. Could It possibly be that we face less stress？ Maybe we've found other ways to deal with it. Or maybe we just feel embarrassed.

(33)

A．To keep your eyes a bit drier.

B．To protect your eyes from infection,

C．To cry for your sadness only.

D．To conceal your happiness.

ving things. Plants, fish, dinosaurs, and people are made of atoms and molecules, but they are put together in a more complicated way than the molecules in the primitive ocean. What's more, living things have energy and can reproduce, while the chemicals on the Earth 4 billion years ago were lifeless.

After years of study, scientists figured out that living things, including human bodies, are basically made of amino acids, nucleotide bases, lipids and water. How could such complicated molecules have been formed and have started to interact in the primitive soup？ Scientists were stumped.

Then, in 1953, two scientists named Harold Urey and Stanley L. Miller did a very simple experiment to find out what had happened on the primitive Earth. They set up some tubes and bottles in a closed loop, and put in some of the same gases that were present in the atmosphere 4 billion years ago—water vapour, ammonia, carbon dioxide, methane, and hydrogen.

Then they shot an electric spark through the gases to simulate bolts of lightning on the ancient Earth, circulated the gases through some water, sent them back for more sparks, and so on. After several days, the water that the gases had been bubbling through turned brown. Some new chemicals were dissolved in it. When Miller and Urey analyzed the liquid, they found that it contained amino acids—the very kind of molecules found in all living things.

When did scientists come to realize how the atoms and molecules on the Earth mostlikely combined to make living things？

A．4 billion years ago.

B．After seven days.

C．Many years ago.

D．In 1953.

【71】Unfortunately the chances of any animal become a fossil are not very great, and【72】the chances of a fossil then being discovered many thousand of years later are even less.【73】It is not surprising that all the millions of animals that have lived in the past【74】we actually have fossils of only very few.

【75】There are several ways into which, animals and plants may become fossilized.【76】First, it is essential that the remains are buried, as though dead animals and plants are quickly destroyed【77】if they remain exposed the air. Plants rot, while insects and hyenas eat the flesh and bones of animals. 【78】Finally, the few remaining bones soon disintegrate the hot sun and pouring rain. If buried in suitable conditions, however, animal and plant remains will be preserved. 【79】The same chemicals change sand and silt into hard rock will aim enter the animal and plant remains and make them hard too.【80】When this happens, we say that they become fossilized.

(71)

Recently more and more attention has been focused to S1. ______

the problem of preserving the environment. The fact that a

Government Ministry being called the Department of the S2. ______

Environment has been created shows how unimportant the S3. ______

issue is considered to be.

Over the past thirty years or so the quality of many

people's lives have deteriorated in some respects because of S4. ______

technological progress. Those people living near airports are

constantly attacked by the noise of increasingly larger and

more powerful jet aircraft taken off and landing. The motor S5. ______

car has been responsible for many changes in the

environment. On the one hand it has brought mobility to

millions of people, but on the other it has taken rise to the S6. ______

construction of more noisy roads and has polluted the

atmosphere with exhaust fumes. While towns and cities have

become larger and uglier and more dense populated the S7. ______

rural areas have lost most of their population owing to the

need for less workers in agriculture. The countryside has S8. ______

also been affected by the large scale use of insecticides.

For one thing the killing of insects has resulted from a loss S9. ______

of balance in the ecology. Many people are afraid that fruit

and vegetables sprayed with chemicals may have some

poisonous effect on the people who eat it. S10. ______

【S1】