globules(小球)of one liquid evenly distributed throughout another.The difference lies in what's in the globules and what's in the surrounding liquid，says Brocklehurst，who led the investigation.In cream，fatty globules and what's in the surround ing liquid，says Brocklehurst，who led the investigation.In cream，fatty globul es drift about in a sea of water.In butter，globules of a watery solution are l ocked away in a sea of fat.The bacteria which make the food go bad prefer to li ve in the watery regions of the mixture.”This means that in cream，the bacteria are free to grow throughout the mixture，”he says.When the situation is revers ed，the bacteria are locked away in compartments (密封仓) buried dee p in the sea of fat.Trapped in this way，individual colonies cannot spread and rapidly run out of nutrients.They also slowly poison themselves with their wast e products.”In butter，you get a self - limiting system which stops the bacteri a growing，”says Brocklehurst.The researchers are already working with food com panies keen to see if their products can be made resistant to bacterial attack t hrough alterations to the food's structure.Brocklehurst believes it will be pos sible to make the emulsions used in salad cream，for instance，more like that in butter.The key will be to do this while keeping the salad cream liquid and not turning it into a solid lump. 36. The significance of Brocklehurst's research is that ______ . A) it suggested a way to keep some foods fresh without preservatives B) it discovered tiny globules in both cream and butter C) it revealed the secret of how bacteria multiply in cream and butter D) it found that cream and butter share the same chemical composition 37. According to the researchers.cream sours faster than butter because bacteria_____ . A) are more evenly distributed in cream B) multiply more easily in cream than is butter C) live on less fat in cream than in butter D) produce less waste in cream t han in butter 38. According to Brocklehurst，we can keep cream fresh by ______ . A) removing its fat B) killing the bacteria C) reducing its water content D) altering its structure 39. The word“colonies”(Line 2，Para.4) refers to ______ . A) tiny globules B) watery regions C) bacteria communities D) little compartments 40. Commercial application of the research finding will be possible if s alad cream can be made resistant to bacterial attack ______ . A) by varying its chemical composition B) by turning it into a solid lump C) while keeping its structure unchanged D) while retaining its liquid form
Part ⅢVocabulary and Structure(20 m inutes)
Directions: There are 30 incomplete sentences in this part.For each sentence there are four choices marked A)，B)，C) and D) .Choose the ONE answer that best completes the sentence.Then mark the corresponding letter on the Anwer Sheet with a single line through the centre. 41. She ought to stop work；she has a headache because she ______ too long. A) has been reading B) had read C) is reading D) read 42. Niagara Falls is a great tourist ______ drawing millions of visitors every year. A) attention B) attraction C) appointment D) arrangement 43. I don't mind ______ the decision as long as it is not too late. A) you to delay making B) your delaying making C) your delaying to make D) you delay to make 44. The hopes goals，fears and desires widely between men and women，between the rich and the poor. A) alter B) shift C) transfer D) vary 45. Corn originated in the New World and thus was not known in Europe until Columbus found it ______ in Cuba. A) being cultivated B) been cultivated C) having cultivated D) cultivating 46. The sale usually takes place outside the house,with the audience _____ on benches， chairs or boxes. A) having seated B) seating C) seated D) having been seated 47. This kind of glasses manufactured by experienced craftsmen ______ comfortably. A) is worn B) wears C) wearing D) are worn 48Some diseases are _____ by certain water animals. A) transplanted B) transformed C) transported D) transmitted 49. Wouldn't you rather your child _______ to bed early? A) go B) went C) would go D) goes 50. Although Anne is happy with her success she wonders _____ will hap pen to her private life. A) that B) what C) it D) this 51. The words of his old teacher left a _____ impression on his mind.He is still influenced by them. A) long B) lively C) lasting D) liberal 52. Mike's uncle insists ______ in this hotel. A) staying not B) not to stay C) that he would not stay D) that he not stay 53. We agreed to accept ______ they thought was the best tourist guide. A) whatever B) whomever C) whichever D) whoever 54. It is our ______ policy that we will achieve unity through peaceful means. A) consistent B) continuous C) considerate D) continual 55. Between 1974 and 1997，the number of overseas visitors expanded ______ 27%. A) by B) for C) to D) in 56. Although many people view conflict as bad，conflict is sometimes useful it forces people to test the relative merits of their attitudes are behaviors. A) by which B) to which C) in that D) so that 57. He is ______ about his chances of winning a gold medal in the Olymp ics next year. A) optimistic B) optional C) outstanding D) obvious 58. Sometimes I wish I ______ in a different time and a different place . A) be living B) were living C) would live D) would have lived 59. The director was critical ______ the way we were doing the work. A) at B) in C)of D) with 60. In a sudden ______ of anger，the man tore up everything within reac h. A) attack B) burst C) split D) blast 61. ______ she realized it was too late to go home. A) No sooner it grew dark than B) Hardly did it grow dark that C) Scarcely had it grown dark than D) It was not until dark that 62. In Britain people ______ four million tons of potatoes every year. A) swallow B) dispose C) consume D) exhaust 63. I'd ______ his reputation with other farmers and business people in the community， and
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