题目内容

Why does cream go bad faster than butter? Some researchers think they have the answer,and it 1        down to the 2        of the food,not its chemical composition―a finding that could help 3        some processed foods of chemical preservatives (防腐剂) .

Cream and butter 4        pretty much the same substances,so why cream should sour much faster has been a mystery. Both are emulsions (孚L状液) 一tiny globules (小球体) of one liquid evenly distributed throughout another. The difference 5        in what's in the globules and what's in the surrounding liquid,says Brocklehurst,who led the 6      .

In cream,fatty globules drift 7        in a sea of water. In butter,globules of a watery solu?tion are locked away in a sea of 8.        The bacteria which make the food go bad 9        to live in the watery regions of the mixture. "This means that in cream,the bacteria are 10        to grow throughout the mixture," he says.

When the situation is 11       ,the bacteria are locked away in compartments (间隔室) bur?ied deep in the sea of fat. 12       in this way,individual colonies cannot spread and 13        run out of nutrients (养料) .They also slowly 14        themselves with their waste products. "In but?ter,you get a selflimiting system which stops the bacteria 15       ," says Brocklehurst.

The researchers are already working with food companies 16        to see if their products can be made resistant 17        bacterial attack through alterations to the food's structure. Brockle?hurst believes it will be possible to 18        the emulsions used in salad cream,for instance,more like 19        in butter. The key will be to do this while keeping the salad cream 20        and not turning it into a solid lump.

(   ) 1. A. puts   B. turns   C. takes   D. comes

(   ) 2. A. variety   B. content   C. quality   D. structure

(   ) 3. A. help   B. relieve   C. rid   D. discharge

(   ) 4. A. contain   B. include   C. cover   D. enclose

(   ) 5. A. remains   B. stays   C. shows   D. lies

(   ) 6. A. investigation   B. survey   C. exploration   D. inspection

(   ) 7. A. away   B. about   C. over   D. off

(   ) 8. A. globules   B. cream   C. fat   D. water

(   ) 9. A. wish   B. choose   C. prefer   D. decide

(   ) 10. A. free   B. likely   C. busy   D. exhausted

(   ) 11. A. opposite   B. reversed   C. returned   D. advanced

(   ) 12. A. Caught   B. Trapped   C. Seized   D. Captured

(   ) 13. A. tightly   B. slowly   C. firmly   D. rapidly

(   ) 14. A. murder   B. poison   C. pollute   D. release

(   ) 15. A. decreasing   B. changing   C. growing   D. raising

(   ) 16. A. anxious   B. keen   C. clever   D. unwilling

(   ) 17. A. in   B. of   C. on   D. to

(   ) 18. A. make   B. take   C. design   D. create

(   ) 19. A. those   B. ones   C. that   D. it

(   ) 20. A. liquid   B. vapour   C. substance   D. fresh

DDCAD     ABCCA  BBDBC    BDACA

为什么奶油比黄油坏得快?一些研究者认为他们有了答案,这归因于食物的结构,而不是其化学成分——这一新发现可以帮助某些加工食品摆脱防腐剂。

1. D come down此处的意思是"答案就在于";而turn down是"调低,关小,拒绝";take down是"记下,写下,拆掉,拆台";put down 是"镇压,记下"。

2. D强调的是食物本身的分子结构而不是其化学成分造成的变化。

3. C摆脱即不使用。 rid为正确答案。

5. D lie in是固定短语,表示问题就在于……

6. A investigation调查;survey口头或问卷调査;exploration探查;inspection视察。

7. B drift away (人) 渐渐离开,(烟雾等) 慢慢散去;drift about无定向移动,飘来飘去;drift over不是搭配的词组;drift off (人) 渐渐离开。

9. C此句的意思是:使食物变坏的细菌喜欢生活在这种混合物水域内。由此可知应选C。

10. A free to grow可理解为到处滋生的意思。

11. B reverse也就是"反过来"的意思。

12. B除了B(陷人) ,其他选项都是"捕获"的意思。

13. D此处意思为"快速耗尽养分"。

14. B毒害自己。

15. C根据前文可知,此处为"阻止细菌繁殖" 的意思。所以要选C。

16. B anxious,eager,keen这些形容词均有"急切的,渴望的"之意。 anxious:强调因忧虑、关注或害怕而产生的急切心情。 eager: 侧重于急于成功的迫切心情。 keen:强调因兴趣强烈或欲望而急于做某事。

17. D词组resist to为固定搭配。

18. A make something cream保持液态状态。

19. C避免重复用that代替前面提到过的乳脂。

20. A 对比后面的into solid可知前面应是keep ...liquid.故答案应选A.

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"It's warm,it's fun and it won't break the bank (耗尽资源) "goes the ad for a wellknown package holiday group. The top billing given to temperature in the slogan illustrates just how im?portant climate is to holidaymakers. It's one of the first things you notice when you step off the plane―part of the " sense of place" which academics talk about.

Australia is a big country,stretching from the tropics to the roaring forties,and it has a correspondingly wide range of climates. There's something to suit everyone!Scubadivers like the warm waters off the tropical Queensland coast;sunlovers feel at home in central Australia's hot,dry climate. The cool temperate climate of the Australian Alps in the southeast of the conti?nent attracts skiers in winter and walkers in summer.

What is the best time of year to visitAustralia? It depends on what part of the country you will be visiting and what you would like to do. If you can stay for several months,you can plan your trip to catch the best weather everywhere.

Australia can be divided into six main climatic regions or zones on the basis of air tempera?ture and humidity. Our map shows where each region is. A description of each region's climate is given below,from the viewpoint of someone accustomed to a temperate climate. People from tropical climates will tolerate the heat better than indicated in the zone descriptions,but will feel less comfortable in the cooler parts of the country. The climate zones are:

(   ) 1. In which of the following media does this passage mostly appear?

   A. Fiction. B. TV programme. C. Newspaper. D. Website.

(   ) 2. When is the best time of year to visit Australia?

   A. In summer. B. It depends.

   C. In winter. D. All the year around.

(   ) 3. Which part of Australia attracts ski lovers in winter?

   A. TheAustraliaAlps. B. The southwest of the continent.

   C. The southeast of centralAustralia. D. The northeast ofAustralia.

(   ) 4. What is the best title for this passage?

   A. Travelling inAustralia   B. Climate Tips for Travellers inAustralia

   C. Welcome toAustralia   D. The Best Time to VisitAustralia

Some plants get so hungry they eat flies,spiders,and even small frogs. What's more amazing is that these plants occur naturally (in special environments) in every state. In fact,they're found on every continent except Antarctica.

You've probably seen a Venus' flytrap (捕蝾草) .It's often sold in museum gift stores,de?partment stores,and even supermarkets. A small plant,it grows 6 to 8 inches tall in a contain?er. At the end of its stalks (茎) are specially modified leaves that act like traps. Inside each trap is a lining of tiny trigger (触发) hairs. When an insect lands on them,the trap suddenly shut. Over the course of a week or so,the plant feeds on its catch.

The Venus' flytrap is just one of more than 500 species of meateating plants,says Barry Meyers-Rice,the editor of the International Carnivorous Plant Society's Newsletter. Note: Despite any sciencefiction stories (科幻小说) you might have read,no meateating plant does any danger to humans.

Dr. Meyers-Rice says a plant is meateating,only if it does all four of the following: " at?tract,kill,digest,and absorb" some form of insects,including flies,butterflies,and moths. Meateating plants look and act like other green plants―well,most of the time.

All green plants make sugar through a process called photosynthesis (光合作用) .Plants use the sugar to make food. What makes " meateating" plants different is their bugcatching leaves. They need insects for one reason;nitrogen (氮) .Nitrogen is a nutrient that they can't obtain by any other way. Why?

Almost all green plants on our planet get nitrogen from the soil. " Meateating" plants can't. They live in places where nutrients are hard or almost impossible to get from the soil be?cause of its acidity (酸度) .So they've come to rely on getting nitrogen from insects and small animals. In fact,nutrientrich soil is poisonous to "meateating" plants. Never fertilize (施肥) them!But don't worry,either,if they never seem to catch any insects. They can survive,but they'll grow very slowly.

(   ) 1. What is a Venus flytrap?

   A. It is a small plant which grows in a container.

   B. It grows 6-8 inches tall.

   C. It can attract,kill,digest and absorb some form of insects.

   D. It is a kind of plant which gets hungry easily.

(   ) 2. What can we learn from the passage?

   A. It is the bugcatch leaves make Venus flytrap different from other plants.

   B. All green plants get nitrogen from the soil.

   C. " Meateating" plants are found on every continent.

   D. Some "meateating" plants in the world do danger to humans.

(   ) 3. Why does the writer say "Never fertilize ' meateating' plants?"

   A. Though growing slowly,they don't need nitrogen.

   B. Probably because the source of nitrogen is adequate.

   C. Simply because the nutrientrich soil will do harm to them.

   D. Perhaps they can get fertilize by themselves.

(   ) 4. Which of the following might be the best title for the text?

   A. Meateating Plant Does No Danger to Humans

   B. Let These Plants Swat (重击) the Bugs for You

   C. No Need to Fertilize Meateating Plants

   D. No Insects,No "Meateating" Plants

Many of the home electric goods which are advertised as liberating the modern woman tend to have the opposite effect,because they simply change the nature of work instead of eliminating it. Machines have a certain novelty (新奇的) value,like toys for adults. It is certainly less tiring to put clothes in a washing machine,but the time saved does not really amount to much:the machine has to be watched,the clothes have to be carefully sorted out first,stains removed by hand,buttons pushed and water changed,clothes taken out,aired and ironed. It would be more liberating to pack it all off to a laundry and not necessarily more expensive,since no capital in?vestment is required. Similarly,if you really want to save time you do not make cakes with an electric mixer,you buy one in a shop. If one compares the image of the woman in the women's magazine with the goods advertised by those periodicals,one realizes how useful a projected im?age can be commercially. A careful balance has to be struck; if you show a laboursaving de?vice,follow it up with a complicated recipe on the next page;on no account hint at the notion that a woman could get herself a job,but instead foster her sense of her own usefulness,empha?sizing the creative aspect of her function as a housewife. So we get cake mixes where the cook simply adds an egg herself,to produce "that lovely homebaked flavour the family love",and knitting patterns that can be made by hand,or worse still,on knitting machines,which became tremendously fashionable when they were first introduced. Automatic cookers are advertised by pictures of pretty young mothers taking their children to the park,not by professional women presetting (预先设置) the dinner before leaving home for work.

(   ) 1. What does the underlined word " eliminating" mean?

   A. Wiping out. B. Doing away with. C. Throwing out. D. Carring off.

(   ) 2. What is the shortcoming of the home electric goods advertised as liberating the mod?ern women according to the author?

   A. They have absolutely no value for the housewives.

   B. They really save the housewife very little time.

   C. They save the housewife's time but not her money.

   D. The can remove unpleasant aspects of housework.

(   ) 3. In the writer's opinion,the goods advertised in women's magazines are really meant to         .

   A. free housewives from housework

   B. encourage housewives to go out to work

   C. make housewives into excellent cooks

   D. give them a false sense of fulfillment

(   ) 4. What is the main meaning of this passage?

   A. Consuming anything just relying on the basic need not the advertising.

   B. Tremendous fashion can't bring you a certain novelty value.

   C. Advertising is reliable and always describes things true to the fact.

   D. Women have to redouble their efforts to get the real liberation.

I just finished taking an evening class at Stanford. The last lecture was on the mindbody connection―the relationship between stress and disease. The speaker (head of psychiatry (精神病学) at Stanford) said,among other things,one of the best things that a man could do for his health is to be married to a woman,whereas for a woman,one of the best things she could do for her health was to nurture (培育) her relationships with her girlfriends. At first everyone laughed,but he was serious.

Women connect with each other differently and provide support systems that help each other to deal with stress and difficult life experiences. Physically this quality "girlfriend time" helps us to create more serotonin一a neurotransmitter (神经传递素) that helps combat depression and can create a general feeling of well being. Women share feelings whereas men often form relationships around activities. They rarely sit down with a buddy (伙伴) and talk about how they feel about certain things or how their personal lives are going. Jobs? Yes. Sports? Yes. Cars? Yes. Fishing,hunting,golf? Yes. But their feelings? Rarely. Women do it all of the time. We share from our souls with our sisters,and evidently that is very good for our health. He said that spending time with a friend is just as important to our general health as jogging or working out at a gym.

There's a tendency to think that when we are "exercising" we are doing something good for our bodies,but when we are hanging out with friends,we are wasting our time and should be more productively engaged―not true. In fact,he said that failure to create and maintain quality personal relationships with other humans is as dangerous to our physical health as smoking!So every time you hang out to schmooze (闲谈) with a gal pal,just pat yourself on the back and congratulate yourself for doing something good for your health!We are indeed very very lucky. So let's toast to our friendship with our girlfriends. Evidently it's very good for our health.

(   ) 5. It can be concluded that women tend to share feelings to deal with stress whereas men

   A. often sit down with a friend to talk about their feelings

   B. seldom share their feelings of depression with friends

   C. sometimes exchange their feelings about personal lives with friends

   D. always do different activities to combat depression with friends

(   ) 6. The underlined phrase "working out" in the second paragraph most probably means

   A. figuring out the algebra problems 

   B. puzzling out the answer to the problem 

   C. doing physical exercise  

   D. solving the difficult problem

(   ) 7. The purpose of the first paragraph is to show that         .

   A. marriage is good for men while relationships with girlfriends essential for women to be healthy

   B. it is a best thing for men and women to get married in order to keep healthy

   C. the speaker was serious to talk about the relationship between stress and disease

   D. one of the best things women could do for health was to nurture the relationships with boyfriends

(   ) 8. What can we learn from the last paragraph?

   A. "Exercising" good for our bodies, "hanging out" wasting our time.

   B. A disagreeable relationship with other persons is similarly dangerous to our health.

   C. We have reasons to toast to the friendship with our girlfriends.

   D. Hanging out with friends should be more productively engaged.

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