Recent results on the helicity structure of the nucleon from HERMES
泛读2U8课外阅读
Passage 8 (Unit 8, Book II: Getting Enough Sleep? Dream on. Health)Is it any wonder that America is also a country of dangerously overweight people?According to a recent study by the National Center for Health Statistics, the number of adults characterized as overweight in the United States has jumped to an astonishing one-third of the population. Overweight in this case means being about 20 percent or more above a person’s desirable weight. Since the figures for “desirable weight”have moved upward over the last decade or so, total poundage – even at 20 percent over – may be considerable.So are the attendant health risks. Excess weight has been linked to cardiovascular disease, hypertension, adult-onset diabetes and some forms of cancer, among other diseases.Once, when work and school and the grocery store were a two-mile hike away, Americans could afford the calories they consume. But not now, not when millions spend four or five hours a day in front a TV set – along with a bag of chips, a bowl of buttered popcorn and a six-pack –and there’s a car or two in every driveway.“There is no commitment to obesity as a public health problem,”said Dr. William Dietz, director of clinical nutrition at the New England Medical Center in Boston. “We’ve ignored it, and blamed it on gluttony and sloth.”If one definition of a public health problem is its cost to the nation, then obesity qualifies. According to a study done by Dr. Graham A. Colditz, who teaches at Harvard Medical School, it cost America an estimated $68.8 billion in 1990. But what’s wrong blaming it on gluttony and sloth? True, some unfortunate overweight people have an underlying physical or genetic problem. But for most Americans, the problem is with two of the seven deadly sins.Losing weight is a desperately difficult business. Preventing gain, however, is not. Consumer information is everywhere, and there can be few adults who truly believe that hot dogs, fries, a soda and a couple of Twinkies make a good lunch. But they eat them anyw ay.As more and more Americans became educated to the risks of smoking, more and more Americans gave up the habit. Now it appears that Americans need an intensive education in the risks of stuffing themselves and failing to exercise as well.Given the seductiveness of chocolate and cheese, the couch and the car, that habit will be hard to break. But if an ounce of prevention can obviate a pound of fat, it is well worth the struggle.1. The author sets up the standard of overweight people based on the fact that _____________.A. the number of overweight people has astonishingly increasedB. people have a different idea about their desirable weight nowC. overweight becomes a threat to people’s healthD. the overweight problem has long been studied2. By saying “So are the attendant health risks”, the author means __________.A. America suffers health risks as well as the overweight problemB. health risks resulted from overweight are serious tooC. overweight is classified as one of the health problemsD. people have also pay much attention to the possible health risks3. What does William Dietz think of overweight?A. Overweight should be treated as a public health problem.B. Overweight should be attributed to gluttony and sloth.C. Overweight has much to do with nutritional problems.D. Overweight has nothing to do with the overuse of cars.4. Most Americans believe that __________.A. the overweight problem has cost the nation muchB. obesity is related to one’s physical conditionsC. people who are overweight are unfortunateD. gluttony and sloth are two deadly sins5. In order to solve the overweight problem, the author suggests that everyone need to __________.A. be taught to prevent gaining weightB. be educated to lose weight effectivelyC. seek help from consumer informationD. know what makes a healthy dinner。
On distinguishing quotients of symmetric groups
The notation used is fairly standard. We use κ, λ, µ, and ν to stand for cardinals (usually infinite), and |X | for the cardinality of the set X . If Ω is any set we write Sym(Ω) for the group of all permutations of Ω (1–1 maps from Ω onto itself), with permutations acting on the right, and we write S (µ) for Sym(µ) for any cardinal µ. For g ∈ Sym(Ω) we let supp g be the support of g . If we are working in Sλ (µ)/Sκ (µ) (where Sλ (µ), Sκ (µ) are as introduced above) then we refer to sets of cardinality less than κ as small. We use overlines such as x to stand for finite sequences (‘tuples’) (x1 , x2 , . . . , xn ). By a permutation representation or action of a group G we understand a homomorphism θ from G into Sym(X ) for some set X . The representation is faithful if θ is 1–1, it is transitive if for any x, y ∈ X there is g ∈ G such that x(gθ) = y , and it is trivial if its image is the trivial group. If X is a subset (or sequence of elements) of a group G, we let X denote the subgroup generated by X . If g, h ∈ G we write g h for the conjugate h−1 gh of g by h. If g is a sequence of members of G and h ∈ G, we write g h for the h sequence whose ith entry is gi , and if g, h are sequences of members of G of the same length, we let g ∗ h be the sequence whose ith entry is gi hi . If gh 1 = g 2 for some h, g1 and g2 are said to be conjugate. If N ≤ G and f = (f1 , . . . , fn ) ∈ Gn we let N.f = (N f1 , . . . , N fn ). We write P (X ) for the power set of the set X , and Pκ (X ) for the set of subsets of X of cardinality less than κ. Then P (X ) is a boolean algebra, and each Pκ (X ) for κ infinite is a ring of sets. Moreover, if ℵ0 ≤ κ < λ ≤ |X |+ , Pκ (X ) is an ideal of Pλ (X ), so we may study the quotient ring Pλ (X )/Pκ (X ), which is a boolean algebra just in the case where λ = |X |+ (that is, where Pλ (X ) = P (X )). In the remainder of this introductory section we give an outline of the main arguments of the paper. Our analysis of the quotient groups Sλ (µ)/Sκ (µ) is carried out using certain 2 many sorted structures Mκλµ and Nκλµ . (There is also a simpler version M∗ κλµ of Mκλµ applicable just in the case cf (κ) > 2ℵ0 .) These structures are devised with the object of describing the permutation action of tuples of elements of Sλ (µ), modulo small sets. The essential properties of such an n-tuple g = (g1 , g2 , . . . , gn ) are described by its action on the orbits of the subgroup g . In fact, if g1 and g 2 are n-tuples of elements of Sλ (µ) then g1 and g2 are conjugate if and only if the orbits of g 1 and g 2 can be put into 1–1 correspondence in such a way that the action of g1 on each orbit of g1 is isomorphic to that of g 2 on the corresponding orbit of g2 . Similar remarks apply in the quotient group, except that we have to allow fewer than κ ‘mistakes’ (by passing to equivalence classes of a suitable equivalence relation). These considerations lead us to observe that what should represent g in Mκλµ is a list of how many g -orbits there are of the various possible isomorphism types, where by ‘isomorphic’ here we mean ‘under the action of g’. Included among the sorts of Mκλµ are therefore, for each positive integer n, the family ISn of isomorphism types of pairs (A, f ), where f is an n-tuple of 3
【高中英语】人教版2019选择性必修第二册Unit 1 SCIENCE AND SCIENTI练习题
人教版2019选择性必修第二册Unit 1 SCIENCE AND SCIENTISTS Period One Reading and Thinking(2476)1.N o wad a ys D a ta S is an imp o r ta n t ma jor a t un ive r s it y.2.O n e c an s ee g e r ms cle a r ly u n d e r a s u itab le m.3.With e n ou gh p,th e jud g e s en te n ce d tha t c r imin a l to de a th.4.We ha ve m s o lu tio n s to th is q u es tio n, th o ug h it is a little d iff ic u lt.5.Yo u'd b e tte r h a ve p wa te r o r b o iled wa te r s o a s n o t to be ill.6.D o b e c a r e fu l wh ile (操纵)th is f a s t cu ttin g too l.7.We a re ag a in s t a n y f o r m o f(干涉)in o u r in te r n a l a ff a ir s.8.N o w ma n y a(家庭) h a s o n e o r mo r e pr iva te c a r s.9.N e ve r ge t (沮丧的)wh e n yo u c a n't g e t a h igh e r p o s ition fo r th e time b e in g.10.E a ch o f u s live s a lif e o f (相互矛盾的)tr u th.11.J a ck wa s in ju r ed too(s e ve r e)in the ac c id en t to mo ve.12.In th e e a r ly 19th c en tu r y, c h o le r a b ro k e ou t in Eu r op e, (le a d) to millio n s o f d e a th s.13.D ea th s ma y o c c u r in th e e a r ly o r la te s tag e s o f th e (in f ec t).14.T he d yin g b o y wa s f in a lly s a ve d th a nk s th e f a mo u s d oc to r.15.C ho le r a,on e o f the mo s t f e a r e d d is ea s e s, is J oh n S no w de sir e d to d e s tro y.16.S o fa r,with e ve r yo n e's e ff o r ts,th e a ir pollu tio n in th is c ity(d e c re a s e)a lo t.17.T he po lic e th o ug h t th e r e we r e th r e e (s u s p ec t)in th e q u es tio n ed pe o p le.18.T h is ma na g e r no w h a s ma n y d iff ic u lt p r ob le ms(ha nd le).19.T he p ro b le m c an be s o lve d o nc e a n d a ll,if yo u do tha t.20.It tu r n ed ou t tha t th e wa te r in f ec te d b y wa s te wa s (b la me)f o r th e o u tb r e ak o fc h o le ra.21.短语填空lin k…to…, on the d e cr e a s e, on c e an d fo r a ll, b e in fe c te d with, tr an s f o r m in to, s ub s c r ibe to,th an k s to, b e b la me d f o r(1) Tak e c a re o f yo u r s e lf. Tr y n o t an y d is e a s e.(2) T he E ng lis h C ha nn e l E ng la nd th e ma in la nd o f Eu r ope.(3)the ir g r ea t te amwo r k,th e p r o je c t was c o mp le te d on time.(4) T ha t yo u n g ma n h is ca r e le s sn e s s in wo r k ye s te r d a y.(5) T h is time we mu s t g e t the ma c h ine r ep a ir e d.(6)Mo s t me mb e r s th is p r o g ra mme,s o it wa s pa s s ed.(7) We a r e h a vin g a d iff ic u lt time,f o r ou r sa le s a re no w.(8)In d iff e r e n t te mp er a tu r e s, th ing s ca n an o the r s ta te.22.the y will b r in g in mo r e a d va nc e d tale n ts.(表语从句)他们的计划之一是他们要引进更多的高级人才。
高三英语询问科学单选题50题
高三英语询问科学单选题50题1. Recent research has found that some bacteria can form a complex community structure called a biofilm. In a biofilm, bacteria are surrounded by a self - produced matrix. Which of the following is a major component of this matrix?A. DNAB. ProteinC. LipidD. Carbohydrate答案：D。
解析：在生物膜的基质中，碳水化合物是主要成分之一。
选项A，DNA虽然存在于细胞中，但不是生物膜基质的主要成分。
选项B，蛋白质是生物膜的组成部分，但不是基质的主要成分。
选项C，脂质主要参与细胞膜结构构建，而非生物膜基质的主要部分。
本题主要考查生物科学知识，语法上是一般现在时的陈述语句。
2. The mitochondria are known as the "powerhouses" of the cell. Which process mainly occurs in mitochondria?A. PhotosynthesisB. GlycolysisC. Cellular respirationD. Protein synthesis答案：C。
解析：线粒体中主要发生的过程是细胞呼吸，这是其重要功能。
选项A，光合作用主要发生在叶绿体中。
选项B，糖酵解发生在细胞质中。
选项D，蛋白质合成主要发生在核糖体上。
从语法来看，这是一个考查一般现在时和生物知识结合的题目。
3. In the process of evolution, some animals have developed unique adaptations. The giraffe's long neck is an example. Which theory best explains the evolution of the giraffe's long neck?A. Lamarck's theory of inheritance of acquired characteristicsB. Darwin's theory of natural selectionC. Mendel's law of inheritanceD. The theory of punctuated equilibrium答案：B。
新视野第二册期末词汇题练习题
新视线第二册词汇题练习题Unit 11. Although most birds have only a negligible sense of smell, they have ____ vision.A. vigorousB. exactC. acuteD. vivid2.A complete investigation into the causes of the accident should lead to improved standards and should ____ new operating procedures.A. result inB. match withC. subject toD. proceed with3.The government has devoted a larger slice of its national ____ to agriculture than most other countries.A. resourcesB. potentialC. budgetD. economy4.The ____ of last week’ s examination is not announced yet.A. resultB. consequencesC. effectD. conclusion5.They tried to ___ hard plastics for metals in manufacturing machine parts.A. replaceB. substitute（代替品）C. take the place ofD. give way toing the right hand to shake hands is a(n)____.A. conventionB. inheritanceC. traditionD. habit7.Scientists study the ___ between parents and their babies to better understand how infants learn.A. interchangeB. interrelationC. intercourseD. Interaction（互相作用）8.A nurse has many duties to ___ in caring for the sick.A. achieveB. completeC. fulfill （达成）D. finish9.I ’ d his reputation with other farmers and business people in the community, and then make adecision about whether or not to approve a loan.A. take into account（重视、谅解）B. account forC.make up forD. make out10.A long-term study ___ by the medical school shows that babies of smoking mothers will be lesshealthy than those of nonsmoking mothers.11.The government has devoted a larger part of its national ___________ to agriculture than most othercountries.A. resourcesB. potentialC. budgetD. economy12.In western countries, it is the _________ for men to wear suits on formal occasions.A. convictionB. conventionC. confessionD. concession13.The annual income of school teachers in this place was __________ at $ 900.A. budgetB. predictedC. accountD. assessed14.His long illness and _____________ absence put him far behind in his study.A. sequentB. consequentC. frequentD. subsequent15.If you want to learn English, you must first find a ____________ teacher.A. ableB. desirableC. competent（称职、适合）D. significant16.Jane was the only one who ___ all the conditions: she was of the required age, height and degree.A. fulfilledB. recoveredC. appreciatedD. rejected17.We ______ his idea for a music club, and decided to have an art club instead.A. turnedB. rejectedC. acceptedD. isolated18.I appreciate ________ herself to the cause of education..A. of her devotingB. her to devoteC. her devotingD. to devote19.It is most ________ that he attend the conference.A. desirousB. desiringC. desiredD. desirable（理想的、满意的）20._____ his wealth , he is not happy .A. Except forB. In spite ofC. Because ofD. Beside21.She couldn ’ t hide her _______ at his foolish mistake.A. amusementB. fascinationC. hostilityD. recognition22.The publisher ’ s ______ of his manuscript depressed him.A. ejectionB. rejectionC. injectionD. dejection23.It is highly desirable that every effort _______to reduce pollution in Beijing.A. was madeB. be madeC. will be madeD. would be made24.He is an artist, so these economic terms are not familiar _________ him.A. withB. ofC. toD. on25.Happiness does not necessarily ________ wealth.A. go afterB. go withC. go onD. go outUnit 21. I rang the hotel to ____ a double room for a week.A. reserveB. conserveC. preserveD. occupy2.These special interest groups represent such _______ viewpoints as consumerism, environmental protection, for and against the equal rights amendment(修正案), social reform, anti-business, pro-business, and even anti-tax increase.A. diverseB. divorceC. reverseD. converse3.The coastline has been hit by a ___ of violent storms.4.He burns a(n) ___ to win a fame.A. emotionB. sensationC. ambitionD. indignation5.Many doctors ___ upon a diet which contains a lot of fat.A. frownB. crownC. drownD. brown6.Five out of ten posts falling ___ are being kept empty.A. vacuumB. vacant（空缺的）C. vainD. vagueputer Science is an ________ subject for law students at our university.A. openB. optionC. opticalD. optional8.London is one of the important ________ centers of the world.A. economicB. financialC. financeD. economical9.The country has a(n) _________ of skilled workers, but not enough jobs.A. abundance（丰裕）B. qualityC. plentyD. lotcation in government colleges is very cheap, but if you go to the_______colleges, it is muchmore expensive.11.Bicycles are regarded as an _________alternative to buses whose fares have increased 5 times in thepast 3 years.A. economicB. economicalC. economicsD. economized12. He says what he thinks, __________ other people’ s feelings.A. regardless ofB. by virtue ofC. in case ofD. with regard to13.The president, together with his wife ____ coming to the small town next week.A. areB. willC. isD. would be14.We must see the ________ as well as the obverse side of things.A. inverseB. diverseC. converseD. reverse（颠倒的）15. We took ______________ from the storm in a barn.A. shadeB. shelterC. shadowD. sheath16.________ use of alcohol may lead to distortion of thinking and abnormal illusions.A. SuccessiveB. Excessive（过分的）C. ProgressiveD. depressive17.He was suggested to ___________on smoking in order to relieve his respiratory problem.A. cut inB. cut outC. cut upD. cut down18. Gambling is viewed as an open ______ that is prevailing in the community.A. crimeB. offenceC. vice（道德败坏的人）D. habit19.A leopard（豹） never changes its ________.A. stripesB. stainsC. spotsD. dots20. This class is only _____________with English language.A. relatedB. have doC. concernedD. dealt21. He has just passed CET IV and he decided that passing CET VI will be his next _________.A. targetB. purposeC. budgetD. gadget22.No estimate has been done on the __________ of SARS on the economy of China and some otherAsian countries as well.A. affectB. defectC. impact（冲击、影响）D. compact23.A speaking contest will be held by the Students Union next month, which is to be ___________ byPhilips China.A. helpedB. aidedC. sponsoredD. financedUnit 31.I can ______ some noise while I’ m studying, but I can’ t stand loud noises.A. come up withB. catch up withC. put up withD. keep up with2.Pupils who pass the test will be ______to the next grade.A. promoted（学生升级）B. proceededC. progressedD. projected3.Our company decided to ______the contract because a number of the conditions had not been met.A. cancelB. resistC. assumeD. destroy4.New York is ______second in the production of apples, producing 850,000,000 pounds this year.A. placedB. occupiedC. arrangedD. classified5.Knowing something as a whole is far from knowing all its ______ .A. instanceB. characterC. itemsD. details6.He was ______of having asked such a silly question.A. sorryB. guiltyC. ashamedD. miserable7.______emergencies I have found it easier not to expect any help from the other people.A. BesidesB. Except forC. Rather thanD. Instead of8.I have been ______with that company for several years.A. supplyingB. treatingC. concerningD. dealing（分派）9.I am sorry I ______ your glasses off the desk when I was wiping it.A. drewB. hitC. struckD. knocked10.Some old people don ’ t like pop songs becausetheycan’ t so much noise.A. resistB. intendC. tolerateD. hurt11.Have you ever imagined___________ in the air?A. to flyB. flyingC. having flownD. fly12.Our racial and cultural difference ___our friendship and taught us a great deal about life.A. enhanced（加强）B. demotedC. eliminatedD. updated13.A good dictionary can tell the _______ distinctions between meanings of synonyms.A. clearB. subtle（奇妙的）C. acuteD. sharp14.Television sometimes has a negative ______ on children.A. affectB. effectC. perfectD. defect15.The ringing bells _____ the news of the birth of the prince.A. claimedB. proclaimedC. releasedD. published16.It is not allowed to ______ the forbidden area.A. interchangeB. adjacentC. approachD. decorate17.A young mother was shouting to his son in a_______ voice.A. dashB. harsh（严苛的）C. crashD. rush18.The interview______ in a most friendly atmosphere.A. processedB. precisedC. proceededD. preceded19.He is a/an_______ husband.A. contributedB. attributedC. devotedD. demoted20.The soloist gave a/an ______ performance and won a loud applause from his audience.A. brilliantB. brightC. awfulD. notorious21.If he had worked harder last year, he ____ admitted to a better university.A. will beB. would beC. would have beenD. were22.A. Have you ever tried ____ smoking ?B. No, I never tried ____ smoking, but I ever tried ____ a pipe.A. to give up/to give up/smokingB. giving up/to give up/smokingC. to give up/giving up/to smokeD. giving up/to give up/to smoke23. You are so kind a person. I really appreciate _______.A. youB. what you have done for meC. for your helpD. all of you24. Do you know VCD stands for Video _____ disc? And VCR stands for Video Cassette Recorder?A. compatibleB. compressC. compact（简短的）D. contract25. It is one of the duties of police to _______the public order.A. deserveB. conserveC. reserveD. preserveUnit 41. I have not heard anything from him since his ______.A. departure（离世）B. faultC. foundationD. acceptance2. As a chairman for nearly ten years, Professor Smith has never _______ to anything.A. beardB. attachedC. granted（认可）D. kept3.These programs are designed for those young people who want to _______ higher education but do not have enough time to go to university.A. insure B .purse C. purchase D. pursue（持续）4.Since he often travels on business, he can _______ himself to sleeping in any place he can find.A. makeB. accustomC. forceD. let5.Much of the news provided by this newspaper is _______, not foreign.A. domestic（国的）B. strainC. purchaseD. murder6.Even though he has lived in China for many years, Mark still can not _______ himself to the Chinese customs.A. adoptB. advertiseC. adaptD. accept7. During these ten years, many new methods have been _______ in the field of foreign language teaching.A. adoptedB. adaptedC. alarmedD. aided8. The _______ is nearly dead , so I can not start the car again.A. beanB. beamC. bakeD. battery（电池）9. Alan is a good football player and never breaks _______.A. legalB. regulationsC. limitationD. agreement10.The dog _______ the rabbit but could not catch it.A. ceasedB. chainedC. checkedD. chased（追捕）11.Our factories are _______first-class technical men.A. angry withB. needed ofC. starved ofD. lacked of12.The Personnel Manager ______ down the list of names of the applicants.A. staredB. gazedC. glancedD. peered13.The government gave us a _______ to build another classroom.A. budgetB. moneyC. allowanceD. grant14.I am _____________ to sleeping late.A. goodB. accustomedC. fondD. like15. She is not a competent driver and can’ t ____ with driving in heavy traffic.A. tackleB. handleC. copeD. do16. He _______ himself to the cold weather.A. adaptedB. usedC. adoptedD. rejected17.“ The more dangers we _______, the harder should we push forward.”A. counterB. encounter（遇到）C. countD. enforce18. Einstein was really a great man who is able to ________ everyone’ s respect.A. orderB. requestC. commandD. require19. He spends 2,000yuan on train ____ every year.A. mareB. fairC. pareD. fare20. A written word is a sign of a certain sound, and sound is ______ the sign of an idea.A. by turnB. in returnC. in turnD. on the turn21. We had a _______ night at the theater last night.A. tremendousB. trembleC. templeD. tempo22. ________ space surrounds the Earth.A. DefiniteB. CountlessC. EndlessD. Infinite23. The doctor __________ him to smoke.A. asksB. suggestsC. forbidsD. bans24. The general public _______ to the use of drugs.A. rejectB. objectC. againstD. opposeUnit 51.We’ ll ____ you for any damage done to yourhouse while we are in it.A. filterB. hookC. swallowD. compensate（赔偿）2. I am not sure whether I can gain any profit from the investment, so I can’ t make a(n) ____ promise to help you.A. variableB. poisonousC. definite（明确的）D. pregnant3. His salary ____ between $3,000 and $4,000 a month.A. underminesB. fluctuates（颠簸）C. slipsD. batters4. Martin made a ____ donation to our fund.A. greedyB. promptC. gradualD. generous（大方的）5. Although cats cannot see in complete darkness their eyes are much more ____ to light than humaneyes.A. boundB. sensitiveC. slimD. grateful6.He has a(n) ____ to get angry if he is criticized.A. accommodationB. contradictionC. tendency（趋向）D. advertisement7. The statesman has never ____ his stand for human rights.A. starvedB. weakenedC. assignedD. submitted8. Children who are over-protected by their parents may become ____ .A. spoiled（惯坏）B. harmedC. hurtD. damaged9. The secretary didn’ t dare to ____ her general manager though she knew she was right.A. pick upB. lean onC. give inD. stand up to（英勇面对）10. The author attempted to write with plain words ____ humor.A. packed withB. coupled withC. dressed inD. died from11 . She decided to ____ the job when she found that the company needs constant overtime work.A. leaveB. give inC.quitD. escape12.I want to give up because Ican’ t see a _____chance of success.A. slipB. slimC. tinyD. few13.This clock _____ five minutes a day.A. getsB. winsC. makesD. gains14.I lost my wallet and now I am ______ penniless（囊空如洗的） .A. literally （完整）B. literarilyC. directlyD. completely15. In Britain people ________ four million tons of potatoes every year.A.swallowB. disposeC. consumeD. exhaust16. Did you see a ___ of keys on a blue ing?r I forgot where I put them and now can’ t go back homeA. packageB. bunchC. seriesD. group17.Please wait at the school gate. John will _____you _______there.A. pick upB. take upC. pick onD. take on18.Although I expected that she might not come but when she did fail to show up I still felt ___ disappointed.A. somehowB. sometimeC. some timesD. somewhat19.The company promised _________ delivery but we didn receive’the goods now two months later.A. instantB. rapidC. fastD. prompt（立刻）20.The rapid development of communications technology is transforming the _________in whichpeople communicate across time and space.A. moodB. mannerC. missionD. vision21.Unable to swim, she watched _____ as the child struggled in the water.A. hopefullyB. usefullyC. hopelesslyD. helplessly22． Against such a well-trained professional team,I ’m afraid our chances of winning the game are pretty ______.A. noticeableB. weakC. slimD. helpless23.It ’s difficult for a short-sighted person to _____ a needle from the ground.A. pick outB. pick upC. pick overD. pick on24.I was a little disappointed with him because what he did does more to _____ the problem than to solve it.A. fastenB. stiffenC. hardenD. weaken25.She used to store her favorite _____ in her notebook while reading world-famous masterpieces.A. brandsB. quotations （语录）C. advertisementsD. manufacturers26.They were _____ by hunger and climbing became difficult.A. hardenedB. weakenedC. softenedD. strengthened27.The trees on both sides of the toad provide ______ for people in summer.A. protectionB. zoneC. shelterD. poison28.I bought her a ______ of flowers in the market.A. bunchB. packageC. packD. gang29.She never stopped talking, which made me _____ impatient.A. literallyB. worldlyC. scarcelyD. hardly30.when Betty writes, she always keeps a dictionary _____.A. out of handB. in handC. by handD. at hand31.The incident her resolve to leave the company.A.hardenedB. changedC. persuadedD. encouraged32.The system is providing help for old people.A. pointed atB. supposed toC. began toD. directed at32.The exploitation had the building ’s foundations.A. hardenedB. weakenedC. broadenedD. darkened34.He told her a pack of lies, but she it whole.A. acceptedB. refusedC. believedD. swallowed （轻信）35.I have a whole of stuff to do this morning.A. groupB. plentyC. bunchD. team36.He sent her some books, a dictionary.A. carried withB. coupled withC. filled withD. fetched with37.He was that she didn’ttell his parents about the incident.A. forgetfulB. gratefulC. regretfulD. careful38.This effect is particularly in younger patients.A. noticeableB. acceptableC. desirableD. agreeable39. We from the rain in a doorway.A. stoppedB. shelteredC. preventedD. escaped40. They are hundreds of prize s to win.A. literallyB. eventuallyC. largelyD. extremely41. The ladder the wall, making it easy for the thieves to enter the house.A. stood forB. stood upC. stood againstD. stood onUnit 61.Have you made out your _____ for a passport?A. appointmentB. applyC. definitionD. application2.I had every _____in my secretary; she would do the right thing.A. knowledgeB. qualificationC. beliefD. confidence3.His father does not_______ of her going to study in the United States alone.A. proveB. approveC. agreeD. award4.We all believe he is qualified ______the job.A. inB. withC. atD. for5.He gave up his study in college in _______ because of his illness.A. repairB. despair（无望）C. displayD. despite6.It ’ s very difficult to _____ the meaning of a word without a context.A. resolveB. defineC. determineD. decide7.Professor Baker told me that this bottle was _____ as poison.A. signedB. labeled（贴标签）C. laboredD. determine8. Designing houses is an intelligent job, but George can easily make it _______.A. intelligenceB. intelligentC. intellectual（感动他人理智的）D. intellectually9. He could not ______ the crime any longer.A. conceiveB. conceal（隐蔽）C. concedeD. confide10.Tom______ the bag as his by telling what it contained.A. identifiedB. recognizedC. showedD. indicated11.Honey can___________ sugar in this recipe.A. institute （协会）B. substitute（取代）C. constitute（构成）D. destitute（缺少）12.Your question is a little general, could you make it a little ___ so that it will be easier for me toanswer.A. specialB. speciallyC. specializedD. specific13.Jack and Bill are twins, but the_______is taller than the former.A. laterB. lateC. firstD. latter14.So far, we have found only one candidate who is _____________ for the job.A. efficientB. qualifiedC. intelligentD. capable15.He wanted to join the army but was ________ because of his poor health.A. turned downB. turned offC. turned awayD. turned out16._______ what extent can we trust him?A. ForB. AtC. ToD. By17.It is very ______ of you to make all the necessary arrangement for me.A. considerable（该注意的）B. considerateC. thoughtfullyD. thankful18.He was ________ Nobel Prize for his achievement in literature.A. rewardedB. paidC. awardedD. devoted19.What you said yesterday is not ________ with what you said just now.A. constantB. insistentC. persistentD. consistent20.The toys on the stand were so ______ to the little kid that he refused to go.A. amusingB. terrifyingC. invitingD. fascinated21.The children in remote parts of the country still have no _______ to internet.A. accessB. wayC. useD. approach22.As it turned _______ later, he was an old friend of my mother.A. offB. outC. awayD. down23.Some _____ diseases are caused by the genes.A. giftedB. inherentC. artificialD. coherent24.It seems that young children have less prejudice _________ each other than adults do.A. forB. withC. againstD. on25.This custom still ________among members of the older generation.A. popularB. prevails（流行）C. dominatesD. has26.The lady dressed in the latest Paris fashion is _____ in her appearance but rude in her speech.A. elaborateB. excessiveC. elegant（优雅的）D. exaggerated27.In production, cheaper materials are being ______ for the better, more expensive kind.A. discardedB. replacedC. convertedD. substituted28.These small white houses are _____ of the Greek islands.A. peculiarB. specialC. characteristicD. exclusive29.The observer’s statement about the accident was very ______; we know almost every thing aboutit now.30.Some years ago the city became divided into tow separate cities. The former is now the center of tradeand finance, and the _____ seat of government.A. lastB. latterC. laterD. late31.Fluency in three languages _____ her for work in the European Parliament.A. qualitiesB. enablesC. creditsD. deserves32.Mr. Bloom is not _____ now, but he will be famous someday.A. significantB. dominantC. magnificentD. prominent(突出的 )33.I ’m pleased to have made your ______.A. acquaintance（心得）B. acknowledgmentC. friendD. familiarity34.The man in the corner ______ to having told a lie to the manager of the company.A. declinedB. refuseC. acceptedD. confessed35.Three university departments have been _____$600000 to develop good practice in teaching andlearning.A. promotedB. securedC. includedD. awarded36.They prepared a synthetic rubber as a substitute for the natural rubber that they could no longerobtain.A. substanceB. discoveryC. distanceD. replacement37.The government of every country should _____ great importance to environmental protection.A. attachB. approachC. payD. spend38.Mr. Smith will be ______ the office next week when the manger is away.A. in response ofB. in charge ofC. charged withD. responsible of39. I was so angry that I _____ throwing something at him.A. wanted likeB. felt likeC. would likeD. looked like40. There are one or two lines more on this application form which you must _____.A. fill inB. hand inC. put inD. take in41. an individual bird can ____ the call of its own species.A. specifyB. differC. inviteD. identify42. John and James are brothers. The former is a teacher; the ____ is an engineer.A. laterB. lastC. latterD. second43. To ____ as a doctor you have to study a long time and pass exams.A. prepareB. qualifyC. trainD. satisfy44. The Dutch language was closely _____ to German.A. relatedB. relativeC. concernedD. regarded45. I ’llcall the restaurant to ____ a table for us.A. leaveB. emptyC. reserveD. preserve46. Mr. Johnson ____ the teacher who was in hospital.A. took place ofB. replace forC. substituted forD. instead of47. I applied for the job but they turned me ____ because I didn’tknow German.A. offB. downC. awayD. back48. The management _____ all factory employees a five percent pay increase.A. rewardedB. forwardedC. awardedD. reserved49. Gestures can ____ the message to those who lost their hearing.A. containB. conveyC. confessD. combine50. Is this game meant for a _____ age-group?A. specificB. specialC. especialD. particular51. I think you should get a job ____ to stop yourself getting so bored at homeA. only ifB. if onlynotC. let aloneD. as forUnit 71.The city seems ______ tonight, as if something is going to happen.A. nervousB. restlessC. tenseD. tight2.The teacher puts ______ on listening and speaking.A. attentionB. interestC. emphasisD. importance3.Do what you are told and don’ t ____ me.A. argue withB. argue againstC. argue aboutD. argue into4.The story _____ her sympathy for those who were suffering from the flood.A. excitedB. stirredC. movedD. stuck5.Reading is not a kind of relaxation for him but an _______for his feeling.A. outingB. outletC. exitD. path6.I can ______ him to you for the job. He is a very good worker.A. suggestB. recommendC. adviseD. stimulate7.In western countries, young people are more independent ______ their parents.A. fromB. ofC.offD. to8.I missed the train and _____ was late for school.A. finallyB. eventuallyC. subsequentlyD. consequently9. Testing the new-model plane is a _______ job, but he decided to devote himself to it.A. profitableB. hazardous(危险的 )C.well-paidD. hasty10.He drove fast and arrived an hour ____ of schedule.A. in advanceB. aheadC. abreastD. in front11.Hard work together with perseverance_________ to his success.A. attributedB. distributedC. contributedD. devoted12.His film caused a _________ in America.A. stingB. Stir（动乱）C. stunD. stitch13.The committee recommends he_______ the new financial manger.A. will beB. isC. shall beD. be14.There are always some parts of your life ______ which you can have little or no control.A. throughB. overC. forD. by15.People concerned about cholesterol levels are suggested to___________ on meat.A. cut awayB. cut offC. cut downD. cut in16.The job _______ traveling abroad for three months each year.A. involvedB. includedC. consistedD. concluded17.You can ’ t get there ______ by swimming.A. more thanB. asC. less thanD. other than18.It is not interesting at all, ________it is extremely boring.A. on the other handB. instead ofC. on the contraryD. in contrast19.He ________ knowing anything about the corruption.A. refusedB.rejectedC. desiredD. denied20.As the saying goes: the end justified the ______.A. meanB. methodsC. meansD. ways21.Some patients were_______ because the beds were needed by new patients.A. discharged（走开）B. firedC. laid offD. gave out22.Life- long ______ to one ’ s company is advocated in the Japanese society.A. commentB. commitment（效劳）C. promiseD. guarantee23.This office has a very modern_______ though it has an old-fashioned appearance.A. exteriorB. interior （部）C. superiorD. inferior24.The hunter set a _______ for the animal and finally caught it.A. placeB. trickC. trapD. net25. The international community imposed________ on that country for its terrorist actions.A. banB. sanctions(制裁 )C. attackD. prohibition 26. _____ with my duties,I sometimes have a strong urge to escape from them..A. EnrichedB. OverwhelmedC. PreoccupiedD. Inspired27. Just in the middle of his speech, his head began to_____ and he fainted.A. turnB. rotateC. spin（转）D. move28. The men spent all day _____ water out of the flooded houses..A. absorbingB. suckingC. forcingD. pumping29. The nation must follow its own policy and not be influenced by _____ events.A. exteriorB. extraC. inferiorD. interior30. A good boss always ____ responsibility to his assistants.A. removesB. delegates（委派）C. refersD. leases31. The arguments are over now, and we hope no one will _____ them up again..A. stirB. boilC. disturbD. interfere32. Sports provides a(n) _____ for a teenager’s feelings of aggression or frustration.A. exitB. exhaustC. outletD. leak33. The problems requiring immediate solution will be given _____ at the meeting..A. priority （优先）B. urgencyC. superiorityD. emergency34.Water evaporates 蒸(发 ) into the air to make clouds. The same water then comes back to the earthas rain. Such a repetition is a form of water ____ .A. cycleB. courseC. circleD. circuit35. During the American Civil War, many people in the South were forced to____ their homes.A. withdrawB. withstandC. fleeD. fleet36. A quick mind enabled him to _______ swiftly in an emergency.A. actionB. reactionC. interactD. react37. The atmosphere around the central square was very _______.A. tendB. tenseC. tentD. tender38. The doctor recommended that he _______ a few more days in the hospital.A. stayingB. stayedC. should stayD. to stay39. The crisis had a _______ effect on the economy.A. destroyB. destructionC. destructiveD. destructor40. The program can only be successful if the students _______ training as important.A. perceive（意会）B. persevereC. percentD. perceptive41. She is going on a diet to get rid of her _______ weight.A. accessB. excessC. exceedD. excessive42. The spoiled girl _______ all her failure to her parents’education.。
新视野大学英语第三版第二册第四单元读写答案KeytoExercisesofB2Unit4
ቤተ መጻሕፍቲ ባይዱ. Words in use
1. confess 3. commence 5. granted 7. displayed 9. lodged
2. tempting 4. coordinating 6. deserved 8. consequently 10. proceed
2. took the initiative 4. thrive on 6. whip out 8. chip in
6.
1. With online learning, there is less study in a regular classroom and more time to spend by yourself.
4. 5Word building
1. qualifications 3. plantations 5. exhibit 7. interpretation 9. illustration 11. identification
2. perception 4. compressed 6. contented 8. complicate 10. extension 12. justification
2. With regular exercise, you’ll have less mental stress and more physical strength.
3. With the new highway, there is less traffic and more comfort for drivers on the road.
5. fall in love with
高中英语学术前沿单选题30题
高中英语学术前沿单选题30题1. In academic research, the data should be analyzed ______ to draw accurate conclusions.A. carefullyB. carelesslyC. quicklyD. slowly答案：A。
本题考查副词的用法。
carefully 表示“仔细地”，在学术研究中，为了得出准确的结论，数据应该被仔细分析。
carelessly 表示“粗心地”，不符合学术研究的要求。
quickly 表示“快速地”，但重点不是速度而是仔细程度。
slowly 表示“缓慢地”，也不符合学术研究追求准确的目的。
2. The scientist ______ a new theory to explain the phenomenon.A. put forwardB. put offC. put upD. put down答案：A。
put forward 意为“提出”，科学家提出新理论来解释这一现象，符合语境。
put off 表示“推迟”；put up 表示“张贴；搭建”；put down 表示“写下；镇压”，均不符合。
3. The experiment was ______ because of the lack of funds.A. cancelledB. continuedC. completedD. controlled答案：A。
cancelled 表示“取消”，由于缺乏资金实验被取消。
continued 表示“继续”；completed 表示“完成”；controlled 表示“控制”，均不符合缺乏资金的情况。
4. The results of the study ______ the previous hypothesis.A. confirmedB. contradictedC. supportedD. ignored答案：B。
高三英语科学前沿动态单选题30题
高三英语科学前沿动态单选题30题1. In the latest scientific experiment, the researchers found that the substance reacts ______ with certain chemicals.A. stronglyB. weaklyC. rapidlyD. slowly答案：A。
本题考查副词的词义辨析。
A 选项“strongly”表示“强烈地”，符合实验中物质反应的程度；B 选项“weakly”表示“微弱地”，与实验情况不符；C 选项“rapidly”侧重速度快；D 选项“slowly”侧重速度慢，均不符合物质与化学物质反应的强度描述。
2. The new scientific experiment aimed to discover how the cells ______ under extreme conditions.A. behaveB. behavesC. behavingD. to behave答案：A。
本题考查动词形式。
“how the cells behave”是宾语从句，从句中主语“the cells”是复数，谓语动词用原形，A 选项正确；B 选项“behaves”是第三人称单数形式，错误；C 选项“behaving”是现在分词形式，不能作谓语；D 选项“to behave”是动词不定式，不能作谓语。
3. During the scientific experiment, they observed that thetemperature ______ steadily.A. roseB. risesC. is risingD. has risen答案：A。
本题考查时态。
“During the scientific experiment”是过去的时间段，要用一般过去时，A 选项“rose”是过去式，正确；B 选项“rises”是一般现在时的第三人称单数形式；C 选项“is rising”是现在进行时；D 选项“has risen”是现在完成时，均不符合过去时间段的语境。
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a r X i v :h e p -e x /0210049v 1 21 O c t 2002RECENT RESULTS ON THE HELICITY STRUCTURE OFTHE NUCLEON FROM HERMESMARC BECKMANNon behalf of the HERMES CollaborationDeutsches Elektronen–Synchrotron DESY,D–22603Hamburg,GermanyE-mail:marc.beckmann@desy.deThe HERMES experiment has measured double spin asymmetries of inclusive and semi–inclusive cross sections for the production of charged hadrons in deep–inelastic scattering of polarised positrons on polarised hydrogen and deuterium targets,in the kinematic range 0.023<x <0.6,and 1GeV 2<Q 2<15GeV 2.For the data taken on the deuterium target,a RICH detector provides the com-plete identification of charged pions and kaons.From the inclusive measurementson deuterium,the polarised structure function g d 1has been extracted with high precision.Together with the semi–inclusive measurements,quark polarisations areextracted separately for the u ,¯u ,d ,¯d ,and (s +¯s )flavours in a LO QCD analysis.Furthermore,a possible breaking of flavour symmetry in the polarised light sea,∆¯u −∆¯d,was measured for the first time and found to be consistent with zero within the experimental precision.1.Formalism of the AnalysisCross section asymmetries measured in doubly polarised deep–inelastic scattering (DIS)provide a useful tool to probe the helicity structure of the nucleon.Under the assumption of a vanishing spin structure function g 2=0,the experimentally measured asymmetry A is related to the asym-metry A 1in the virtual photon –nucleon reference frame byAF 1.(1)Here,D is the depolarisation factor of the virtual photon,g 1and F 1are the polarised and the unpolarised nucleon structure functions,respectively,and ηand γ=2in the systematic uncertainty.In leading order(LO)QCD the relation g1(x,Q2)= q e2q∆q(x,Q2) applies,where∆q(x,Q2)≡q+(x,Q2)−q−(x,Q2)are the helicity quark distributions in the rmation on the charge squared weighted sum over the quark helicity distributions can hence be obtained based on measurements of g1according to Eq.(1).Here,q+(−)(x,Q2)is the number density of quarks with spin aligned parallel(anti–parallel)to the nucleon’s spin.The observation of coincident hadrons from the current fragmentation region in semi–inclusive deep–inelastic scattering(SIDIS)processes pro-vides access to theflavour of the struck quark.Assuming factorisation,the SIDIS cross section asymmetry A h1can be written in LO QCD asA h1(x,Q2)g2=0≃1+R(x,Q2)q e2q q(x,Q2) z max z min D h q(Q2,z)d z.(2)Here,q(x,Q2)denote the unpolarised parton densities(PDFs)and R(x,Q2)=σL/σT is the photo–absorption cross section ratio for longi-tudinal and transverse virtual photons.In this analysis,the fragmentation functions D h q(Q2,z)are integrated over the range z min=0.2to z max=0.8 in z=E h/ν,which is the fraction of the virtual photon’s energy carried by the hadron of type h.The upper cut on z≤0.8eliminates exclusive events from the sample.For a set of measured inclusive and semi–inclusive asymmetries on dif-ferent targets,after integrating over the range in Q2in each x–bin,Eq.(2) can be rewritten in matrix formA(x)=P(x) Q(x).(3) The vectors A(x)and Q(x)contain the measured asymmetries and the po-larisations∆q/q of the different quarkflavours to be extracted,respectively. The elements of the matrix P(x)depend on the fragmentation functions, the PDFs,the cross section ratio R(x,Q2),and on the relativefluxes of hadrons originating from the different nucleons in case of deuterium.P(x) also contains the influence from the limited acceptance of the spectrometer. The fragmentation was modelled in the LUND string model implemented in the JETSET7.4[2]package.In order to obtain a reliable description of the fragmentation at HERMES energies,the LUND string breaking parameters have been tuned tofit the hadron multiplicities measured at HERMES.As an estimate of the associated systematic uncertainties,the analysis was also carried out with an alternativefit to the measured multiplicities and with a default LUND parameter setting for the PETRA e+e−collider.The result-10-410-310-210-1g1dF1d101010101010x<Q2>GeV2-0.6-0.5-0.4-0.3-0.2-0.10.10.2g1d10110<Q2>GeV2Figure1.Preliminary HERMES results for g d1 ing variations of the extracted quarkto the other sources of systematicthe parameterisations of Ref.[3]Theflavour decomposition of the quark solving Eq.(3)for the vector Q(x)= contrast to earlier analyses[4,5],the onlyis∆s(x)/s(x)=∆¯s(x)/¯s(x).2.Experimental ResultsThe HERMES experiment[6]uses the positron beam of the HERA storage ring dinally polarised pure atomic gas targets of A large acceptance forward spectrometer detects the scattered beam positrons hadrons.A RICH detector installed in pions,kaons and protons over a wide polarised deuterium target taken since then.2.1.Inclusive MeasurementsFig.1shows the preliminary HERMES data g d1/F d1and on the polarised structuresults are based on10million events taken4xxxxFigure 2.Preliminary HERMES results on inclusive and semi–inclusive DIS cross sec-tion asymmetries A 1,d (x )on a polarised deuterium target.in the kinematic range Q 2>0.1GeV 2and W 2>3.24GeV 2.Despite the differences in the average values of Q 2 per bin,one observes a good consistency of the HERMES data on g 1/F 1with an earlier measurement of SMC at larger values of Q 2 and measurements at SLAC,taken at similar average values of Q 2.This close agreement is a clear indication for very similar Q 2evolutions for both the polarised and the unpolarised structure functions over the range in Q 2covered by experiments.2.2.Semi–Inclusive MeasurementsThe preliminary data presented here are based on 1.8(6.5)million DIS events taken on a hydrogen (deuterium)target in the kinematic range Q 2>1GeV 2and W 2>10GeV 2.For the hydrogen data set,final statepions could be identified using the information from a threshold ˇCerenkovcounter,while for the deuterium data set the RICH detector provided kaon5x x Figure3.HERMES preliminary results on the polarisation of the u,¯u,d,¯d,and s+¯s quarkflavours versus x(left panel).The right panel shows the results on the correspond-ing polarised quark distributions at a common scale of Q2=2.5GeV2.The dashed and the dotted–dashed lines are parameterisations from Refs.[9,10].The error bars are statistical,while the shaded bands indicate the systematic uncertainties of the results. The contribution labelled”theor.syst.”in the left panel gives the uncertainty due to with the use of two different unpolarised parton densities[3,11].identification as well.The preliminary results for the inclusive and semi–inclusive asymmetries on the deuterium target are shown in Fig.2.Together with a set of inclusive and semi–inclusive asymmetries on a polarised proton target,the polarisation offive quarkflavours was extracted according to Eq.(3).For the sea quarkflavours,at values of x>0.3 the polarisation was set to zero.The resulting small influence on the up and down quark polarisations was included in the systematic uncertainties. Fig.3shows the obtained quark polarisations as well as the polarised quark distributions.The polarisation of the up quarks is positive everywhere in the measured range and increases with x up to0.7at x=0.47.The down quark polarisation ranges between−0.1and−0.5,almost independently of x.For the light sea quarks the polarisation is compatible with zero,while for the strange quarks a slightly positive polarisation is favoured within the measured range in contrast to results based on inclusive data alone(e.g.[9, 10]).However,within their total uncertainty also the polarisation of the strange quarks is zero.Fig.4shows afirst measurement of the difference of the polarised light seaflavours∆¯u(x)−∆¯d(x)together with predictions of a broken SU(2)f6x∆u –-∆d–Figure 4.HERMES preliminary result on the difference of the polarised light sea ∆¯u −∆¯das a function of x at a scale of Q 2=2.5GeV 2.symmetry from Refs.[7,8].The data are consistent with an unbroken SU(2)f symmetry in the light polarised sea.3.ConclusionsHERMES has collected large statistics of inclusive and semi–inclusive DIS data on pure targets of polarised hydrogen and deuterium.From the in-clusive data precise results on the polarised structure function g d1were ex-tracted.Based on a LO QCD analysis of semi–inclusive data taken on bothtarget nuclei,polarised parton densities for u ,¯u ,d ,¯d ,and (s +¯s )flavourshave been extracted as a function of x in the range 0.023<x <0.6.A firstmeasurement of the flavour symmetry in the polarised light sea ∆¯u −∆¯dis compatible with the SU(2)f assumption.References1.Anthony,P.L.et al.,hep–ex/0204028.2.Sj¨o strand,T.,m.82,74(1994).i,H.L.et al.,Eur.Phys.J.C12,375(2000).4.Adeva,B.et al.,Phys.Lett.B 420,180(1998).5.Ackerstaff,K.et al.,Phys.Lett.B 464,123(1999).6.Ackerstaff,K.et al.,Nucl.Instr.Meth.A417,230(1998).7.Dressler,B.et al.,Eur.Phys.J.C14,147(2000).8.Bourrely,C.et al.,Eur.Phys.J.C23,487(2002).9.Gl¨u ck,M.et al.,Phys.Rev.D 63,094005(2001).10.Bl¨u mlein,J.,B¨o ttcher,H.,hep–ph/0203155,Nucl.Phys.B ,(2002)in press.11.Gl¨u ck,M.et al.,Eur.Phys.J.C5,461(1998).。