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For years scientists have been concerned about the effects of air pollution on the earth's natural conditions. Some believe the air inside many houses may be more dangerous than the air outside. It may be one hundred times worse.
Indoor air pollution can cause a person to feel tired,to suffer eye pain, headache and other problems.Some pollutants(污染物)can cause breathing disorders,diseases of blood and even cancer. Most scientists agree that every modern house has some kind of indoor pollution.People began to notice the problem in the early 1970s.It is said that when builders began making houses and offices they did not want to waste energy.To do this,they built buildings that limited the flow of air between inside and outside.They also began using man-made building materials.These materials are now known to let out harmful gases.As the problem became more serious, scientists began searching for a way to deal with it.They discovered a natural pollution control system for building－green plants.Scientists do not really know how plants control air pollution.They believe that a plant's leaves absorb or take in the pollutants.In exchange the plant lets out oxygen through its leaves and through its tiny organizations on its roots.Scientists suggest that all buildings should have one large plant or several small plants inside for every nine square metres of space.Studies of different plants show that each absorbs different chemicals.So the most effective way to clean the air is to use different kinds of plants.Having green plants inside your house can make it a prettier and healthier place.
77.What is the topic of the passage?
A.Air pollution.           
B.Green plants indoors.
C.Indoor air pollution.         
D.Environment protecting.
78.What makes indoor air pollution more harmful than that of the air outside?
A.The limited flow of air indoors.
B.Man-made building materials.
C.Fewer green plants inside houses.     
D.The energy-saving materials indoors.
79.The most effective way to clean the air is to use different kinds of plants because______.
A.they can make houses pettier and healthier
B.they may let out oxygen which people need
C.they can take in all kinds of indoor pollutants  
D.they can absorb different harmful indoor chemicals
80.Which of the following is implied but NOT stated?
A.keep windows open and let fresh air in.
B.Scientists have a clear idea how plants control air pollution.
C.Oxygen is let out through the leaves and roots of the plants.
D.Green plants are a natural pollution control system for building.

閱讀下面短文，從短文后各題所給的四個選項（A、B、C和D）中，選出可以填入的空白處的最佳選項，并從答題卡上將該選項涂黑。

You have waited 45 minutes for the valuable 10 minutes’ break between classes. But when the bell for the next class rings, you can’t   36   how quickly time has passed.

If you are familiar with this   37  , you’ll know how time flies when you are having fun-and  38   when you are bored. Now scientists have   39   a reason why this is the case.

Scans have shown that patterns of activity in the brain   40   according to how we focus on a task. When we are   41  , we concentrate more on how time is passing. And this makes our brains   42   the clock is ticking more slowly.

In an experiment   43   by a French laboratory, 12 volunteers watched an image   44   

researchers monitored their brain activity.

The volunteers were told to   45   concentrate on how long an image appeared for, then

  46   the color of the image, and thirdly, study both duration and color. The results showed that  47   was more active when the volunteers paid   48   subjects.

It is thought that if the brain is   49   focusing on many aspects of a task, it has to  50  its resources, and pays less attention to the clock.  51 , time passes without us really   52   it, and seems to go quickly. If the brain is not so active, it concentrates its   53   energies on monitoring the passing of time.   54  , time seems to drag.

Next time you feel bored   55  , perhaps you should pay more attention to what the teacher is saying!

A．guess                   B．learn                      C．believe                   D．doubt

A．view                    B．point                      C．scene                   D．experience

A．drags                   B．stops                      C．backs                      D．gains

A．thought over         B．made up                 C．suggested                D．come up with

A．change                 B．develop                  C．grow                      D．slow

A．sleepy                 B．bored                            C．excited                   D．active

A．report                  B．think                      C．decide                    D．see

A．produced              B．carried                    C．tried                       D．performed

A．so                        B．when                      C．while                      D．but

A．partly                 B．quickly                   C．how                       D．first

A．remember           B．focus on                 C．forget                     D．tell apart

A．the researchers    B．the experiment        C．the clock                 D．the brain

A．much attention to                           B．more attention to    

C．attention to many                                        D．attention to more

A．busy                  B．likely                            C．ready                      D．sure

A．focus                 B．gather                     C．reach                      D．spread

A．However            B．Furthermore            C．Therefore                D．Finally

A．recognizing        B．watching                 C．noticing                  D．counting

A．enough               B．full                        C．right                       D．proper

A．In fact                B．As a result                     C．For example            D．Instead

A．in class               B．with work               C．in mind                  D．of lessons

The world’s biggest Internet search engine, Google, has proven once again to be king of the Web. Users can download “Google Wi-Fi” software and then enjoy free Wi-Fi service available in some US cities since last Tuesday.
Wi-Fi is short for “Wireless Fidelity”(無線上網). It allows laptop computers and personal digital assistants to connect to the Internet at high speed by radio sigal.
A person with a Wi-Fi enabled computer can connect to the Internet when near one of the network’s access points. The place covered by one or several access points is called a hotspot. Google had already set up two “hotspots” in the US city of San Francisco which provide a free Wi-Fe service.
The Wi- Fi technology even allows users to enjoy a free Internet phone service. Some scientists argue that Wi-Fi may replace mobile phone networks.
Wi-Fi is stioo limited to a few cities, where there are “ hotspots”. But its capability(容量) of sending information has already done better than that of the mobile phone network, even that of 3G (Third Generation telecommunication technology). Some scientists have started to call Wi-Fi 4G.
In addition to a high speed Internet connection, Fi-Fi has other advantages compared to mobile phones. We-Fi is global. The same Wi-Fi system works in different countries around the world. Different from using cell phones, you don’t need to change computers to use Internet phones when you go to other places and most importantly, many Internet phones cost you nothing at all.
【小題1】 Wi-Fi is not available in cities without_____.

   Scientists are building the world’s first thinking robot. It’s true. Some say machines that walk, speak and feel will have been made by 2020.Kismet is the name of a robot which scientists have built this year at the Massachusetts Institute of Technology (MIT)
Kismet is different from traditional robots because it can show human emotions. Its eyes, ears and lips move to show when it feels happy, sad or bored. Kismet is one of the first robots of a new generation that look like human beings and can imitate human feelings.
Some people say that by 2020 we will have created robots with brains similar to those of adult human beings. These robots will be designed to look like people to make them more attractive and easier to sell. What kind of jobs will they do? In the future, robots like Robonaut, a robot invented by NASA, will be doing dangerous jobs, like repairing space stations. They will also be doing more and more of the household work for us. In Japan, scientists are designing robots that will entertain people by dancing and playing the piano.
Meanwhile, people who worry about the future are wondering whether robots will become monsters? Will people themselves become increasingly like robots? Experts predict that more and more people will be wearing micro-computers connected to the Internet in the future. People will have microchips in various parts of their body, which will connect them to a wide variety of small machines. Perhaps we should not exaggerate(夸大) the importance of technology, but one may wonder whether, in years to come, we will still be falling in love, and whether we will feel pain.
Who knows?
【小題1】Kismet is different from traditional robots because______.

We each have a unique genetic (基因的，遺傳的) make-up. Every cell of your body has the same set of about 100,000 separate genes made of DNA. These are the instructions for producing a person. Genes decide everything from the colour of your skin to the way your brain works. You have one of several billion combinations of DNA which come from the random mixing of your parents’ genes. Except for identical twins (同卵雙胞胎), no one has the same combination as another person. You are unique! You are unique in another way too: in the way you are raised and all the experiences you have from before birth to adult life. These experiences influence you, your behaviour and attitudes, and the choices you make.

But are genes or life experiences more important in shaping your appearance and personality? Scientists are studying twins to find out. One set of twins occurs every 70 births---some are identical and others are non-identical twins. Identical twins are special because they share exactly the same genes and often the same environment. Non-identical twins are more like ordinary brothers and sisters.

Some identical twins have been adopted and brought up in different homes. With identical genes but a different home environment, scientists can study twins to see how much a particular feature depends on the genes we inherit. For example, we know that eye problems, like short-sightedness, are mostly genetic. But resistance to pain is largely dependent on experiences. Genes also influence our eating habits. Identical twins brought up apart often like to eat at the same time of day and feel full after eating the same amount. Non-identical twins in similar circumstances have more varied eating habits. Identical twins are also more likely to follow the same patterns for marriage and divorce than non-identical twins.

Scientists are trying to identify the different genes that influence our behaviour. Some people are thrill-seekers and get into risk-taking and adventurous activities. They take up extreme sports like bungee jumping and possibly take drugs. Scientists have discovered a gene which affects this.

We could ask, “Are our lives determined by our genes or our upbringing?” Scientists are learning more all the time, but it is certainly true that both are important in making us who we are.

1.What is the main idea of the first paragraph?

   A. We cannot easily change our physical appearance.

   B. How we turn out depends on our parents’ genes.

   C. Everyone has a physical double somewhere in the world.

   D. Both our genes and our experiences make us who we are.

2.Why are scientists studying twins?

   A. To find out how many twins are born every year.

   B. To discover what shapes us as individuals.

   C. To compare differences between twins.

   D. To study brother-and-sister relationships.

3.According to the passage, __________.

   A. one in 70 twins are genetically identical

   B. non-identical twins are usually not of the same sex

   C. twins separated at birth behave exactly the same

   D. identical twins are genetically the same

4.Which of the following is most affected by experience according the passage?

   A. Eating habits.   B. Eye-sight.   C. Pain resistance.   D. Marriage patterns.

5.What does the underlined “this” in Paragraph 4 refer to?

   A. Our love of sport.             B. Our attitude to risk-taking.

   C. Our skill at bungee jumping.    D. Our ability to take drugs.