Part IWriting课件

1、Part IWriting(30 minutes)Directions: For this part, you are allowed 30 minutes to write a letter. You should write at least 120 words following the outline given below in Chinese."给你的外国朋友写一封信，告诉他(她)你已经被美国的一所大学录取，但你苦恼的是自己的听力和口语水平不够，你想寻求他(她)对于如何提高听力和口语的建议。Part II Reading Comprehension (Skimming a

2、nd Scanning) (15 minutes)The Earth Power and LightCompared to the rest of the universe, the Earth is very small. Our planet and seven others orbit the Sun, which is only one of about 200 billion stars in our galaxy. Our galaxy, the Milky Way, is part of the universe, which includes millions of other

3、galaxies and their stars and planets. By comparison, the Earth is microscopic.Compared to a person, on the other hand, the Earth is enormous. It has a diameter of 7,926 miles ( 12,756 kilometers) at the equator, and it has a mass of about 6 x 1024 kilograms. The Earth orbits the Sun at a speed of ab

4、out 66,638 miles per hour (29.79 kilometers per second). Dont dwell on those numbers too long, though; to a lot of people, the Earth is inconceivably, mind-bogglingly big. And its just a fraction of the size of the Sun.From our perspective on Earth, the Sun looks very small. This is because its abou

5、t 93 million miles away from us. The Suns diameter at its equator is about 100 times bigger than Earths, and about a million Earths could fit inside the Sun. TheSun is inconceivably, mind-bogglingly bigger.But without the Sun, the Earth could not exist. In a sense, the Earth is a giant machine, full

6、 of moving parts and complex systems. All those systems need power, and that power comes from the Sun.The Sun is an enormous nuclear power source-through complex reactions, it transforms hydrogen into helium, releasing light and heat. Because of these reactions, every square meter of our planets sur

7、face gets about 342 Watts of energy from the Sun every year. This is about 1.7 1017 Watts total, or as much as 1.7 billion large power plants could generate. You can learn about how the Sun creates energy in How the Sun Works.When this energy reaches the Earth, it provides power for a variety of rea

8、ctions, cycles and systems. It drives the circulation of the atmosphere and the oceans. It makes food for plants, which many people and animals eat. Life on Earth could not exist without the Sun, and the planet itself would not have developed without it.To a casual observer, the Suns most visible co

9、ntributions to life are light, heat and weather.Night and DaySome of the Suns biggest impacts on our planet are also its most obvious. As the Earth spins on its axis, parts of the planet are in the Sun while others are in the shade. In other words, the Sun appears to rise and set. The parts of the w

10、orld that are in daylight get warmer while the parts that are dark gradually lose the heat they absorbed during the day.You can get a sense of how much the Sun affects the Earths temperature by standing outside on a partly cloudy day.When the Sun is behind a cloud, you feel noticeably cooler than wh

11、en it isnt. The surface of our planet absorbs this heat from the Sun and emits it the same way that pavement continues to give off heat in the summer after the Sun goes down. Ouratmosphere does the same thing-it absorbs the heat that the ground emits and sends some of it back to the Earth.The Earths

12、 relationship with the Sun also creates seasons. The Earths axis tips a little-about 23.5 degrees. One hemisphere points toward the Sun as the other points away. The hemisphere that points toward the Sun is warmer and gets more light-its summer there, and in the other hemisphere its winter. This eff

13、ect is less dramatic near the equator than at the poles, since the equator receives about the same amount of sunlight all year. The poles, on the other hand, receive no sunlight at all during their winter months, which is part of the reason why theyre frozen.Most people are so used to the difference

14、s between night and day (or summer and winter) that they take them for granted.But these changes in light and temperature have an enormous impact on other systems on our planet. One is the circulation of air through our atmosphere. For example:The Sun shines brightly over the equator. The air gets v

15、ery warm because the equator faces the Sun directly and because the ozone layer is thinner there.As the air warms, it begins to rise, creating a low pressure system. The higher it rises, the more the air cools. Water condenses as the air cools, creating clouds and rainfall. The air dries out as the

16、rain falls. The result is warm, dry air, relatively high in our atmosphere.Because of the lower air pressure, air rushes toward the equator from the north and south. As it warms, it rises, pushing the dry air away to the north and the south.The dry air sinks as it cools, creating high-pressure areas

17、 and deserts to the north and south of the equator.This is just one piece of how the Sun circulates air around the world-ocean currents, weather patterns and other factors also play a part. But in general, air moves from high-pressure to low-pressure areas, much the way that high-pressure air rushes

18、 from the mouth of an inflated balloon when you let go. Heat also generally moves from the warmer equator to the cooler poles.Imagine a warm drink sitting on your desk-the air around the drink gets warmer as the drink gets colder. This happens on Earth on an enormous scale.The Coriolis Effect, a pro

19、duct of the Earths rotation, affects this system as well. It causes large weather systems, like hurricanes, to rotate. It helps create westward-running trade winds near the equator and eastward-running jet streams in the northem and southem hemispheres. These wind patterns move moisture and air from

20、 one place to another, creating weather patterns. (The Coriolis Effect works on a large scale-it doesnt really affect the water draining from the sink like some people suppose. )The Sun gets much of the credit for creating both wind and rain. When the Sun warms air in a specific location, that air r

21、ises, creating an area of low pressure. More air rushes in from surrounding areas to fill the void, creating wind. Without the Sun, there wouldnt be wind. There also might not be breathable air at all.Water and FireThe Sun has a huge effecton our water. It warms the oceans around the tropics, and it

22、s absence cools the water around the poles. Because of this, ocean currents move large amounts of warm and cold water, drastically affecting the weather andclimate around the world. The Sun also drives the water cycle, which moves about 18,757 cubic miles (495,000 cubic kilometers) of water vapor th

23、rough the atmosphere every year.If youve ever gotten out of a swimming pool on a hot day and realized a few minutes later that you were dry again, you have firsthand experience with evaporation. If youve seen water form on the side of a cold drink, youve seen condensation inaction. These are primary

24、 components of the water cycle, also called the hydrologic cycle, which exchanges moisture between bodies of water and land masses. The water cycle is responsible for clouds and rain as well as our supply of drinking water.注意：此部分试题请在答题卡1上作答;8-10题在答题卡1上。1. How many Earths could fit inside the Sun?A O

25、ne million. B 93 million. C Two million. D 100 million.2. Earth would not have developed without _A water B fertilizerC soil D the Sun3. What does our atmosphere do?A It absorbs the heat from the ground and sends it to the Sun.B It absorbs the heat from the Sun and emits it back to the Earth.C It ab

26、sorbs the heat from the Sun and emits it the same way.D It absorbs the heat the ground emits and sends some of it back to the Earth.4. _ receives about the same amount of sunlight all year.A The polesB The equatorC The north temperate zoneD The south temperate zone5. Air rushes toward the equator fr

27、om the north and southA because of the dry airB because of the cool airC because of the lower air pressureD because of the higher air pressure6. What doesnt the Corolis Effect cause?A Westward-running trade winds. B Hurricanes.C The water draining from the sink. D Eastward-running jet streams.7. The

28、 Sun has closely relation to create_A wind B the air C soil D fire8. The Sun has a huge effect on_.9. If youve seen water form on the side of a cold drink, youve seen_10. The water cycle is responsible for clouds, rain and_Section BPassage OneQuestions 57 to 61 are based on the following passage.Ove

29、r the last 25 years, British society has changed a great deal-or at least many parts of it have. In some ways, however, very little has changed, particularly where attitudes are concerned. Ideas about social class-whether a person is "working-class" or "middle-class"-are one area

30、 in which changes have been extremely slow.In the past, the working-class tended to be paid less than middle-class people, such as teachers and doctors. As a result of this and also of the fact that workers jobs were generally much less secure, distinct differences in life-styles and attitudes came

31、into existence. The typical working man would collect his wages on Friday evening and then, it was widely believed, having given his wife her "housekeeping", would go out and squander(浪费) the rest on beer and betting.The stereotype ( 陈腔滥调) of what a middle-class man did with his money was

32、perhaps nearer the truth. He wasand still is-inclined to take a longer-term view. Not only did he regard buying a house of these provided him and his family withsecurity. Only in very few cases did workers have the opportunity (or the education and training) to make such long-term plans.Nowadays, a

33、great deal has changed. In a large number of cases factory workers earn as much, if not more, than their middle-class supervisors. Social security and laws to improve century, have made it less necessary than before to worry about"tomorrow". Working-class people seem slowly to be losing th

34、e feeling of inferiority they had in the past. In fact there has been a growing tendency in the past few years for the middle-classes to feel slightly ashamed(惭愧的)of their position.The changes in both life-styles and attitudes are probably most easily seen amongst younger people. They generally tend

35、 to share very similar tastes in music and clothes, they spend their money in having a good time, and save for holidays or longer-term plans when necessary. There seems to be much less difference than in precious generations. Nevertheless, we still have a wide gap between the well-paid (whatever the

36、 type of job they may have and the low-paid. As long as this gap exists, there will always be a possibility that new conflicts and jealousies will emerge, or rather that the old conflicts will re-appear,but between different groups.注意：此部分试题请在答题卡2上作答。57. Which of the following is seen as the cause of

37、 class differences in the past?A Life style and occupation. B Attitude and income.C Income and job security. D Job security and hobbies.58. The writer seems to suggest that the description of_is closer to truth.A middle-class ways of spending moneyB working-class ways of spending the weekendC workin

38、g-class drinking habitsD middle-class attitudes59. According to the passage, which of the following is NOT a typical feature of the middle-class?A Desiring for security. B Making long term plans.C Having priorities in life. D Saving money.60. Working-class peoples sense of security increased as a re

39、sult of the following factor exceptA better social securityB more job opportunitiesC higher living standardD better legal protection61. Which of the following statement is incorrect?A Changes are slowly taking place in all sectors of the British society.B The gap between working-class and middle-cla

40、ss young people is narrowing.C Different in income will remain but those in occupation will disappear.D Middle-class people may sometimes feel inferior to working-class people.Passage TwoQuestions 62 to 66 are based on the following passage.If a mother pushes her small son in a swing (秋千), giving on

41、ly a light force each time he returns, eventually he will be swinging quite high. The child can do this for himself by using his legs to increase the motion, but both the mothers push and the childs leg movements must occur at the proper moment, or the extent of the swing will not increase. In physi

42、cs, increasing the swing is increasing the amplitude ( 振幅 ); the length of the rope on the swing determines its natural oscillation ( 摆动 ) period. This ability of an object to move periodically or to vibrate when stimulated by a force operating in its natural period is called resonance.Resonance is

43、observed many times without consciously thinking about it; for example, one may find an annoying vibration or shimmy in an automobile, caused by a loose engine mount vibrating with increasing amplitude because of an out- of-round tire. The bulge ( 凸出部分) on the tire slaps the pavement with each revol

44、ution; at the natural resonance point of the engine mount, it will begin to vibrate. Such vibrations can result in considerable damage if allowed to persist. Another destructive example of resonance is the shattering of a crystal goblet by the production of a musical tone at the natural resonant poi

45、nt of the goblet. The energy of the sound waves causes vibration in the glass; as its amplitude increases, the motion in the glass exceeds the elasticity of the goblet, and it shatters.An instrument called a tachometer (转速计) makes use of the principle of resonance. It consists of many tiny bars, loo

46、sely fastened together and arranged so that each bar can slide independently of the others. Movement of the bars causes changes in a dial. When placed next to a rotating motor or engine, the tachometer picks up slight vibrations which are transferred to the resonant bars. These bars begin to move, a

47、nd the resulting dial may be read to find the revolutions per minute of the motor very quickly.注意：此部分试题请在答题卡2上作答。62. An object, if moving rhythmically when stimulated in a natural period, is said to _A vibrateB resonateC swingD oscillate63. The distance a swing moves from its resting position is cal

48、led its _A revolutionB movementC frequencyD amplitude64. A tachometer is an instrument that uses resonance to determineA the speed of a motor in revolutionsB the frequency at which a motor vibratesC the amplitude of an engine that oscillatesD the changes in a dial within a car engine65. An annoying

49、vibration can be caused at the natural resonance of the cars engine mount _A if the engine moves too fastB if the engines amplitude increasesC if a tire gets out of balanceD if damage occurs in the engine66. In which of the following cases is it useful to consider the relationship between the length

50、 of an oscillating object and its natural period?A Adjusting the speed of a car. B Adjusting a clock pendulum.C Adjusting tire balance. D Adjusting engine mounts.Part V Cloze (15 minutes)注意：此部分试题请在答题卡2上作答。An adult giraffes head is about six feet above its heart. This means that to 67 enough blood up

51、 to the brain the circulatory 68 must be strong enough to keep the blood at very high pressure.Biologists have known for some time that giraffes solve this problem by having 69 high blood pressure, about 70 that of human beings. But an international team of biologists began to 71 about this. If gira

52、ffes have such high blood pressure, they should have a 72 problem with swelling in their legs and feet. Why dont giraffeshave swollen feet?Giraffes should have 73 problem, too. Every time they bend heads _7_4_ to drink, the blood should 75 to their heads and have a hard time 76 back up (when the hea

53、d is down) to the heart. How come giraffes dont black out when they drink?The answer to the 77 feet problem, the researchers found, is that giraffes have 78 the researchers call a "natural anti-gravity suit". It 79 out that the skinand other 80 in their legs and feet are 81 stiffer and tou

54、gher than those of other 82 . As a result, the blood vessels in the leg cannot swell.Therefore, the blood has nowhere to go but back to the heart. What about blood rushing to the head 83 the giraffe bends down to drink? The researchers found that the giraffes jugular vein, which 84 blood from the he

55、ad back to the heart, has lots of one-way valves in it. In the giraffes neck, there are lots of muscles that flex and relax repeatedly as the animal moves its head and sucks 85 drinking water. By squeezing the valved jugular vein, they 86 blood moving back to the heart even while the animal is drink

56、ing.67.A bringB produceC transferD pump68. A structureB system,C functionD organism69. A unusuallyB generallyC uncomfortablyD commonly70. A halfB multipleC doubleD pair71. A investigateB wonderC undertakeD learn72. A terribleB unreliableC unsolvableD advisable73. A otherB someC othersD another74. A upB downC towardD aside75. A crushB brushC pushD rush76. A followingB returningC flowingD pouring77. A healthyB swollenC drearyD radical78. A whatB whereC thatD those79. A revealsB indicatesC figuresD turns80. A tissuesB vesselsC poresD organs81. A manyB veryC muchD l