String junction as a baryonic constituent

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夸父逐日英语阅读理解

夸父逐日英语阅读理解Title: The Legend of Kuafu Chasing the Sun: An English Reading Comprehension ExerciseIntroduction:The tale of Kuafu chasing the sun is a famous legend from ancient Chinese mythology.This story reflects the human desire to conquer nature and pursue the impossible.In this English reading comprehension exercise, we will delve into the details of this legendary tale and explore its cultural significance.I.Reading Passage:In the ancient times, there was a hero named Kuafu who was known for his strength and determination.He was so confident in his abilities that he decided to chase after the sun, which was believed to be a divine being in charge of lighting up the world.Kuafu started his journey early in the morning, running at a tremendous speed.As the sun rose higher and higher in the sky, he kept running tirelessly.However, the sun was too fast for him, and by noon, it was still far ahead.As the day grew hotter, Kuafu became exhausted and thirsty.He drank from every river and spring he encountered, but it was not enough to satisfy his thirst.Finally, he reached the Yellow River, whichwas vast and deep.He drank the river dry, but still, his thirst was not quenched.In the end, Kuafu collapsed from fatigue and overheating.He perished in his quest to catch the sun.The people admired his courage and determination, and they honored his memory by telling his story for generations to come.prehension Questions:1.Why did Kuafu decide to chase the sun?a) He wanted to prove his strength and determination.b) He wanted to become the sun himself.c) He was jealous of the sun"s power.d) He wanted to bring daylight to the world.2.How did Kuafu feel when he was running?a) He felt energetic and confident.b) He felt tired and thirsty.c) He felt discouraged and wanted to give up.d) He felt like he was getting closer to the sun.3.What did Kuafu do when he reached the Yellow River?a) He swam across the river to continue his chase.b) He drank the river dry to quench his thirst.c) He decided to rest and wait for the sun to come to him.d) He realized the futility of his quest and turned back.4.How did the people remember Kuafu after his death?a) They built a statue in his honor.b) They told his story to future generations.c) They named a constellation after him.d) They organized an annual race to commemorate his journey.III.Answer Key:1.a) He wanted to prove his strength and determination.2.b) He felt tired and thirsty.3.b) He drank the river dry to quench his thirst.4.b) They told his story to future generations.Conclusion:The legend of Kuafu chasing the sun serves as a reminder of human ambition and the desire to overcome nature.Although Kuafu did not succeed in his quest, his determination and courage inspired people for generations.Through this English reading comprehension exercise, we have explored the details of this fascinating tale and gained a deeper understanding of its cultural significance.。

物理数学及其未来 PhysicalMathematicsAndFuture

Preprint typeset in JHEP style-HYPER VERSIONGregory W.MooreAbstract:These are some thoughts meant to accompany one of the summary talks at Strings2014,Princeton,June27,2014.This is a snapshot of a personal and perhaps heterodox view of the relation of Physics and Mathematics,together with some guesses about some of the directions forward in theﬁeld of Physical Mathematics.At least,this is my view as of July21,2014.6.Exploring Quantum Field Theory336.1Classiﬁcation questions336.2Geometry on the space ofﬁeld theories347.String theory compactiﬁcation358.String Field Theory389.Noncommutativity and spacetime3910.Exceptional Structures4011.Should we count in number theory?4112.Keep true to the dreams of thy youth:M-theory4313.Money and jobs4414.An uneasy marriage45Who of us would not be glad to lift the veil behind which the future lies hidden;to cast a glance at the next advances of our science and at the secrets of its development during future centuries?What particular goals will there be toward which the leading mathematical spirits of coming generations will strive?What new methods and new facts in the wide and richﬁeld of mathematical thought will the new centuries disclose?Unlike Strauss,Hilbert then went on,famously,to live up to this magniﬁcent opening with a list of23problems for the20th century.That Problem Set remains incomplete even though it has occupied some of the best talent in Mathematics ever since.Of particular concern to us here is the sixth problem:Durch die Untersuchungen¨u ber die Grundlagen der Geometrie wird uns die Aufgabe nahe gelegt,nach diesem Vorbilde diejenigen physikalischen Disciplinen axiomatisch zu behandeln,in denen schon heute die Mathematik eine hervorragende Rolle spielt...The investigations on the foundations of geometry suggest the problem:To treat in the same manner,by means of axioms,those physical sciences in which mathematics plays an important part....If we(with some generosity)interpret Hilbert’s sixth problem as a search for the ultimate foundations of physics,we can certainly say that one common goal(though not the only goal)in Physical Mathematics is to elucidate the solution to that problem.We are all students of Hilbert.To be sure,Hilbert and his students did not have all the relevant prerequisites!Little could they suspect on that cool and rainy Wednesday,August8,1900,in Paris,that in two short months,on a clear and mild Sunday,October7,in Berlin,Max Planck would guess his famous formula for the energy density of blackbody radiation,and in December derive it using truly revolutionary reasoning.If then,Herr Doktor Hilbert,who possessed such deep mathematical insight,could not read the simplest aspects of the quantum relativistic future in its profounder and more subtle meanings,how may unlettered Ishmael hope to read the awful Chaldee of String Theory’s future?Neither saint nor prophet,I will do what little endeavor I can to elucidate some possible future directions in Physical Mathematics.2.What is Physical Mathematics?I must preface my remarks by describing what I mean by“Physical Mathematics,”a term which seems to confuse many people.Here it is best to take an historical and philosophical approach.I hasten to add that I am neither a historian nor a philosopher of science, as will become immediately obvious to any expert,but my impression is that if we look back to the modern era of science then majorﬁgures such as Copernicus,Galileo,Kepler, Leibniz,and Newton were neither physicists nor mathematicans.Rather they were Natural–3–Philosophers.Even during the18th century and at the turn of the19th century the same could still be said of the Bernoullis,Euler,Lagrange,and Hamilton.But a real divide between Mathematics and Physics began to open up in the19th century.For example in volume2of Nature,from1870,we read of the following challenge from the pure mathematician J.J.Sylvester:What is wanting is(like a fourth sphere resting on three others in contact)to build up the ideal pyramid is a discourse on the relation of the two branches(mathematics and physics)to,and their action and reaction upon,one another-a magniﬁcent theme with which it is to be hoped that some future president of Section A will crown the ediﬁce,and make the plete.James Clerk Maxwell-undoubtedly a physicist-as president of the British Association takes up the challenge in a very interesting address in[292].He modestly recommends his somewhat-neglected dynamical theory of the electromagneticﬁeld to the mathematical community.According to[136]not many mathematicians paid attention,constituting one of the greatest Missed Opportunities of all time.That is not to say thatﬁrst class pure mathematicians of the19th century were not deeply interested in physics.Riemann and Klein are two outstanding examples.In his address to the veryﬁrst International Congress of Mathematicians in Z¨u rich in1897, Henri Poincar´e chose as his topic“Sur les rapports de l’analyse pure et de la physique math´e matique,”(“On the relation of pure analysis to mathematical physics”).He was particularly impressed with Maxwell’s achievement:1Comment ce triomphe a-t-il´e t´e obtenu?C’est que Maxwell´e tait profond´e ment impr´e gn´e du sentiment de la sym´e trie math´e matique; en aurait-il´e t´e de mˆe me,si d’autres n’avaient avant lui recherch´e cette sym´e trie pour sa beaut´e propre?[....]Maxwell en un mot n’´e tait peut-ˆe tre pas un habile analyste,mais cette habilet´e n’aurait ´e t´e pour lui qu’un bagage inutile et gˆe nant.Au contraire il avait au plus haut degr´e le sens intime des analogies math´e matiques.C’est pour cela qu’il a fait de bonne physique math´e matique.How was this triumph attained?Maxwell succeeded because he had become imbued with the idea of mathematical symmetry. Would he have triumphed so well had others before him not explored this symmetry for itsown sake?[...]Analysis was perhaps not among Maxwell’s skills,but to him it would have only been cum-bersome and useless baggage.On the contrary,he was gifted with a profound sense of mathematical analogy.This is why he produced good mathematical physics.These quotations demonstrate that,while theﬁelds of Mathematics and Physics were considered separate,there was still a strong binding between them.Now,the great up-heavals in physics in theﬁrst quarter of the twentieth century only deepened the relation between Physics and Mathematics.In his stunning1931paper(in which he predicted the existence of three new particles-the anti-electron,the anti-proton,and the magnetic monopole)Dirac was both eloquent and exuberant at the very outset[120]:The steady progress of physics requires for its theoretical formulation a mathematics that gets continually more advanced...What however was not expected by the scientiﬁc workers of the last century was the particular form that the line of advancement of the mathematics would take,namely,it was expected that the mathematics would get more and more complicated,but would rest on a permanent basis of axioms and deﬁnitions,while actually the modern physical developments have required a mathematics that continually shifts its foundations and gets more abstract...It seems likely that this process of increasing abstraction will continue in the future...He followed up these prophetic words with great prescience and insight in his1939 Scott Lecture[121].He predicted,correctly,that new domains(and even which domains) of pure mathematics would need to be incorporated into physics:Quantum mechanics requires the introduction into physical theory of a vast new domain of pure mathematics-the whole domain connected with non-commutative multiplication. This,coming on top of the introduction of the new geometries by the theory of relativity, indicates a trend which we may expect to continue.We may expect that in the future further big domains of pure mathematics will have to be brought in to deal with the advances in fundamental physics.Around the same time,Einstein echoed similar sentiments[141]:Our experience up to date justiﬁes us in feeling sure that in Nature is actualized the ideal of mathematical simplicity.It is my conviction that pure mathematical construction enables us to discover the concepts and the laws connecting them which give us the key to the understanding of the phenomena of Nature.Experience can of course guide us in our choice of serviceable mathematical concepts;it cannot possibly be the source from which–5–they are derived;experience of course remains the sole criterion of the serviceability of a mathematical construction for physics,but the truly creative principle resides in mathe-matics.In a certain sense,therefore,I hold it to be true that pure thought is competent to comprehend the real,as the ancients dreamed.There are many other interesting statements and discussions about my theme,but two in particular will play an important role in the remainder of my tale.In1960Wigner waxed philosophical in his famous essay“On the Unreasonable Eﬀectiveness of Mathematics in the Physical Sciences”[395].In1972Freeman Dyson wrote a beautiful essay on the subject,“Missed Opportunities,”[136].In our own time the relation of physics and mathematics is much discussed and debated (and worse)on various blogs and internet sites.One can’t help but think of Ovid’s Four Ages of Man.But something happened between the1930’s,the time of the conﬁdent statements of Dirac and Einstein,and the time of Dyson’s1972essay.For in the latter he famously proclaimed:As a working physicist,I am acutely aware of the fact that the marriage between mathematics and physics,which was so enormously fruitful in past centuries,has recently ended in divorce.Well,I am happy to report that Mathematics and Physics have remarried,but the new relationship has altered somewhat.Indeed,at the very time when Dyson was writing his dire announcement,a sea change in ourﬁeld had begun.Major mathematicians such as Michael Atiyah,Raoul Bott,Graeme Segal,Isidore Singer,and many others,2began to take a more serious interest in physics, especially the physics of gauge theories and string theories.At about the same time,major physicists such as Sidney Coleman,David Gross,Edward Witten,and again,many others, 3started to produce results that called for much greater mathematical sophistication than was needed in the1940’s through the1960’s.It gradually became clear that geometers and mathematically-oriented particle physicists had much to say to one another.The following quote from Raoul Bott’s Plenary Lecture at the AAAS meeting in Boston,1988captures the spirit of the time[57]:Although we still often do not understand each other,the push and pull relationship of our two points of view has never been stronger and has invigorated both of us.Certainly in mathematics the physically inspired aspects of the Yang-Mills theory has had a profound eﬀect on our understanding of the structure of4-manifolds,and I also think we mathe-maticians are only now learning to appreciate the rich mathematical structure of the Diracsea–and indeed of the whole Fermion-inspired world of the physicists,as well as their mystical belief in supersymmetry.And on the other hand the most modern achievements of mathematics-from cobordism to index theory and K theory-have by now made their way into some aspects of present day physics-I think to stay.One thing led to another and,with a great boost from the resurgent interest in string theory,after40-odd years of aﬂowering of intellectual endeavor a newﬁeld has emerged with its own distinctive character,its own aims and values,its own standards of proof.I like to refer to the subject as“Physical Mathematics.”The use of the term“Physical Mathematics”in contrast to the more traditional“Math-ematical Physics”by myself and others is not meant to detract from the venerable subject of Mathematical Physics but rather to delineate a smaller subﬁeld characterized by ques-tions and goals that are often motivated,on the physics side,by quantum gravity,string theory,and supersymmetry,(and more recently by the notion of topological phases in condensed matter physics),and,on the mathematics side,often involve deep relations to inﬁnite-dimensional Lie algebras(and groups),topology,geometry,and even analytic num-ber theory,in addition to the more traditional relations of physics to algebra,group theory, and analysis.To repeat,one of the guiding principles is the goal of understanding the ulti-mate foundations of physics.Following the lessons of history,as so beautifully stressed by Dirac,we may reasonably expect this to lead to important new insights in mathematics. But-and here is the central point of this essay-it is also true that getting there is more than half the fun:If a physical insight leads to a signiﬁcant new result in mathematics, that is considered a success.It is a success just as profound and notable as an experi-mental conﬁrmation from a laboratory of a theoretical prediction of a peak or trough.For example,the discovery of a new and powerful invariant of four-dimensional manifolds is a vindication just as satisfying as the discovery of a new particle.I do not pretend to know the true locus of mathematical reality,but to me such a discovery uncovers an element of truth about our“real world.”But this is as far as I dare venture into the treacherous domain of epistomology.3.String-Math vs.Strings MeetingsThe previous section concluded with what might be considered as a creed for Physical Mathematics.I realize that many physicists will regard the above creed as anathema. This manifesto would have been more enthusiastically embraced as a summary talk in Edmonton,rather than in Princeton,and this highlights a problem.The annual Strings meeting has evolved from an annual meeting on GUTs to Strings 1995,and ever since they have been the premier annual meeting on string theory.But recently,many leading practitioners of Physical Mathematics have seen the need for a separate,more mathematically-oriented conference[373].The resulting String-Math con-ferences beginning at Penn in2011have been a roaring success.Still the creation of an annual String-Math alternative to the Strings conferences should give us pause.Is this a–7–sign of another impending divorce?I hope not.I hope it is a sign of progress and ever-burgeoning diversity,rather than divorce.Still,we might worry that a parting of the ways inevitable?To quote Robert Oppenheimer[332]:This is a world in which each of us,knowing his limitations,knowing the evils of superﬁciality and the terrors of fatigue,will have to cling to what is close to him,to what he knows,to what he can do,to his friends and his tradition and his love,lest he be dissolved in a universal confusion and know nothing and love nothing.There is room for hope:What Oppenheimer does not take into account here are the great syntheses of currents of thoughts into more concise and powerful unifying principles. We need not understand all the intricate details of Leydan jars and the manifold instru-ments in Faraday’s laboratory,thanks to Maxwell’s equations.We must strive for these syntheses in the ever-broadening subject of physics related to string theory and quantum ﬁeld theory.But this cannot happen unless we keep the lines of communication between the two disciplines open.Let me play the role of marriage counselor here:Eachﬁeld should see something to love and respect in the other!I hope that a substantial number of people will continue to go to both Strings and String-Math conferences.I turn now to describing what I believe will be some of the future adventures in Physical Mathematics.4In preparing the following list of problems I have consulted many people for their opinions and received some very useful suggestions.I have also been quite struck by the episodic and fashion-driven nature of ourﬁeld.It is good to bear in mind Dyson’s “Unfashionable Pursuits”[137],and not lose sight of important problems that have been set aside,temporarily.4.Geometry,Symmetry,and PhysicsIn the1980’s H.Garland,I.Frenkel,and G.Zuckerman established a wonderful weekly seminar series at Yale that they aptly called the“Geometry,Symmetry,Physics Seminar.”If we broadly interpret“geometry”to encompass both geometry and topology(especially low-dimensional topology,where“low”means dimension less than12,or so),and we like-wise broadly interpret“symmetry”to encompass algebraic and categorical structures,in addition to group theory and Lie algebra theory,then their title beautifully encompasses some of the deepest themes in the Math-Physics dialogue.Of course,these seminars were not concerned with events only in New Haven but represented fundamental changes occur-ring in Austin,Berkeley,Boston,Cambridge,Chicago,Leningrad,Los Angeles,Moscow, Paris,Oxford,Princeton,Santa Barbara,Utrecht,and many other places.The most spectacular successes and interactions with math have been in the areas of algebra,geometry,and topology.A hallmark of the subject is the astonishing converse of Wigner’s title:The unreasonable eﬀectiveness of physics in the mathematical sciences [30,306].The subject is dauntingly vast.I will limit my comments to just a few possible future paths.4.1Duality Symmetries and BPS statesThe dualities such as homological mirror symmetry and strong weak electric-magnetic du-alities have made spectacular predictions in the interaction between physics and geometry. See,for examples,[29,30].I expect this to continue into the future.4.1.1BPS statesThe problem ofﬁnding the BPS spectrum of aﬁeld theory or string theory is a good touchstone of our understanding of the subject.While the particular number of BPS states of a particular charge is not of special interest,the techniques that must be developed to ﬁnd the spectrum,the generating functions for the spectrum,and the way the spectrum changes,are all of great interest.There has been a lot of progress on this problem for d=4N=2ﬁeld theories.We now have many powerful techniques forﬁnding the spectrum in a large class of examples [18,19,86,185,187,188,191].Nevertheless,we should bear in mind that these techniques fall far short of giving a general prescription forﬁnding the BPS spectrum of an arbitrary d=4N=2theory(in fact,we don’t even know the Seiberg-Witten curve for the general d=4N=2theory!).Even for class S,where there is a simple way of writing the SW curve,the method of spectral networks has yet to be generalized to all ADE(2,0)theories and general surface defects.Similarly,much progress has also been made for the BPS spectrum in“compactiﬁcation”of type II theories on toric Calabi-Yau manifolds.(For a recent sample reference see[86].)Nevertheless,in spite of a great deal of eﬀort there is no algorithmic tool availableﬁnding the BPS spectrum of a single compactiﬁcation of type II string theory on any compact Calabi-Yau,and hence the enduring and diﬃcult open problem remains:Develop tools to compute the BPS spectrum of d=4N=2compactiﬁcations of type II string theory on compact Calabi-Yau manifolds.What is often meant by the BPS“spectrum”is a list of indices,such as the second helicity supertraceΩ(γ)in physics or the Donaldson-Thomas invariants in math.However, for many purposes,we would like to know more about the actual Hilbert spaces of BPS states.We might wish to formulate these as cohomologies of chain complexes.Understand-ing the BPS spectrum at this deeper level is sometimes referred to as“categoriﬁcation”of the spectrum of indices.Some mathematical work on this has been done recently in [62,254].It would be good to have a physical translation of these highly mathematical works.5One natural question to ask in this program is:Categorify the Kontsevich-Soibelman wall-crossing formula[262],together with its2d4d extension[185]for d=4N=2ﬁeld theories,using the physics of BPS states,line defects, and surface defects.With the recent successful categoriﬁcation[190]of the2d Cecotti-Vafa wall-crossing formula[77]I believe this problem could be solved in the near future.6Nevertheless,the solution itself opens up new questions.Interactions of BPS states in d=2N=(2,2)massive theories turn out to have a rich algebraic structure encoded in L∞and A∞algebras and so we must ask:Are there analogous algebraic structures on the spaces of BPS states in higher dimen-sions,in particular in d=4N=2theories?The idea that there are interesting algebraic structures on the set of BPS states is an old dream,which has never been concretely realized except in some special cases[221]. This was motivated by the still-mysterious fact that certain counting functions of BPS states are closely related to denominator products of Borcherds algebras[113,220].One recent concrete proposal has been investigated in detail by Kontsevich and Soibelman[264], but their methods and results have not been carefully related to the actual properties BPS wavefunctions of quiver quantum mechanics.Thus,a relatively straightforward and concrete problem,which should not take too long to solve,would be:Explain in detail the relation of the cohomological Hall algebras of Kontsevich and Soibelman to the BPS states of quiver quantum mechanics.Does it deﬁne an algebraic structure on the space of half-BPS states of d=4N=2theories?4.1.2Topological string theoryA source of an enormous amount of work in Physical Mathematics is topological string theory,ﬁrst deﬁned in[403,406].Topological string theory is often cited as an extremely simpliﬁed version of string theory.If we are ever to have any success with the question:“What is string theory”we shouldﬁrst be able to answer the analogous question for topo-logical string theory.This means we should understand the perturbative theory completely, as well as its nonperturbative completions and the spacetime physics it describes.In the eﬀort to understand topological string theory much attention has focused on the topological string partition function.In the A-model this is deﬁned,as a formal(possibly asymptotic)series by a collection of functions F g on Calabi-Yau moduli space,which are themselves generating functions for Gromov-Witten invariants of genus g curves.This topological string partition function has been the focus of intense research.The famous work of Bershadsky,Cecotti,Ooguri,and Vafa[49]almost provides a recursive deﬁnition but there is a crucial“holomorphic ambiguity,”which has only beenﬁxed up to g≤51in some cases[240].Thus,another enduring problem is:Deﬁne topological string theory on a compact Calabi-Yau manifold nonperturbatively, and use it to compute the higher genus Gromov-Witten invariants for all genera.The computation of F g for all g has essentially been solved by using techniques adapted from the theory of matrix models for the B-model[60]and by using the topological vertex for the A-model in the case of non-compact Calabi-Yau manifolds.In the case of some toric Calabi-Yau manifolds a nonperturbative deﬁnition of topological string theory can in fact be given using matrix models[5],but even in these cases the uniqueness of the nonperturbative extension is not clear.See[288]for a review of the relevant issues.The case of compact Calabi-Yau threefolds seems much more diﬃcult and there are no examples where we can compute all the F g,let alone give a nonperturbative deﬁnition.One approach to the above problems,trying to quantize carefully the Kodaira-Spencer theory of gravity of BCOV has been pursued by Costello,and this might well lead to interesting progress[93].Another extremely interesting attempt to deﬁne nonperturbative topological string theory uses the physics of supersymmetric black holes[331].The most thorough attempt to formulate and prove a sharp version of the OSV conjecture was made in [104],but a completion of the project requires the solution of a number of unsolved problems addressed in the conclusion of[104].One very interesting mathematical prediction that emerged from this and closely related papers[100,175,176]is the following:Fix a very ample class P in a compact Calabi-Yau3-fold.Deﬁne a(mock?)modu-lar form for a congruence subgroup of SL(2,Z)associated to generating functions of DT invariants for boundstates of D4D2D0branes with D4charge P.Some recent mathematical progress on this question has been made in[194,195,380, 381].More broadly,modular properties associated to BPS degeneracies of d=4N=4black holes have been deeply investigated and understood.See[95]for a recent reference.For reasons explained in[281,282]we also expect mock modular forms to play a role in the counting of d=4,N=2black holes,so the important problem remains:Investigate the(mock)modularity properties of generating functions of BPS degenera-cies of black holes in d=4N=2supergravity.4.1.33-manifolds,3d mirror symmetry,and symplectic dualityWe have learned many things about the category of boundary conditions in two-dimensional supersymmetric theories preserving supersymmetry.This leads to the theory of supersym-metric cycles(in math,the theory of calibrated submanifolds),the derived category of coherent sheaves,and homological mirror symmetry.Gaiotto and Witten investigated the half-supersymmetric boundary conditions for N=4SYM and found a rich set of possibilities [177,178,179].It is not known if their classiﬁcation is complete,and this would be a good point to settle.More generally,Extend the Gaiotto-Witten classiﬁcation of supersymmetric boundary conditions to d=4 N=2theories and to d=3theories with extended supersymmetry.As I have learned from T.Dimofte,classifying the category of supersymmetric bound-ary conditions in twisted d=3N=4theories(or at least for some clearly deﬁned class of d=3 N=4theories)should be the key to understanding“symplectic duality,”a mathematical version of the physicist’s“three-dimensional mirror symmetry”[241].4.1.4Knot theoryFor over30years now knot theory has been the source of much interesting Physical Math-ematics.7It continues to provide problems and inspire progress.At present the frontier concerns deﬁnitions of knot homologies,i.e.,chain complexes whose homology groups are invariants of knots in three dimensions and whose Euler characters deﬁne knot polynomials such as those associated to three-dimensional Chern-Simons theory.There are now many approaches both mathematical and physical and so an obvious problem isProvide a uniﬁed viewpoint on the approaches to knot homology of Khovanov-Rozansky [253],Cautis-Kamnitzer[74],Seidel-Smith[359],Kronheimer-Mrowka[266],Webster[389], Gukov-Schwarz-Vafa[214],and Witten[421].Of these various approaches,the most concrete and understandable to a physicist seems to be the gauge-theoretic approach of Witten.It has been further developed in[189],but yet further development is necessary to make the theory more computable,and progress here might ensue from progress on the problem:Investigate the geometry and topology of the moduli spaces of solutions of the Haydys-Witten,the Kapustin-Witten,and the generalized Bogomolnyi equations.In fact,all of these equations are specializations of the Spin(7)instanton equations [84,189,226],and hence the above problem is closely related to those in the next subsection.Much of the work on the categoriﬁcation of knot polynomials has been limited to knots in S3,but an obvious question is whether there is an analogous categoriﬁcation of knot invariants in other three-manifolds.In general,the knot polynomials no longer have integer coeﬃcients so it is not at all obvious what integers one wants to categorify.It is quite possible that physics can provide some very useful guidance here.A relatively straightforward problem is thereforeGeneralize the formulation of eﬀective Landau-Ginzburg theories of[189]to formulate knot homologies for knots in three-folds of the form C×S1where C is a general Riemann surface.The answer to this problem will surely involve the physics of d=4N=2theories of class S where C plays the role of the UV curve and the knots are deﬁned by surface defects.。

拉斯特桑的英语作文

拉斯特桑的英语作文The sun blazed high in the sky, scorching everything in its path. Not a cloud dared to interrupt its reign over the vast expanse of desert. The sand shimmered like gold, each grain a tiny mirror reflecting the relentless heat. Sweat trickled down my back as I trudged through the unforgiving landscape, searching for a shred of shade to shield me from the fiery wrath of the sun.Laughter echoed through the air, mingling with the aroma of sizzling meat and the rhythmic beat of drums. The marketplace bustled with life, a vibrant tapestry woven from a myriad of cultures and traditions. Colorful fabrics fluttered in the breeze, enticing passersby with their intricate designs. I lost myself in the kaleidoscope of sights and sounds, feeling as if I had stumbled upon a hidden oasis of joy amidst the desert's desolation.The ancient ruins stood silent sentinel against the relentless march of time, their weathered stones whisperingtales of forgotten glory. Moss crept like a green blanket over crumbling walls, nature's gentle embrace reclaiming what was once lost to history. I traced my fingers along the intricate carvings, marveling at the craftsmanship of those who had long since turned to dust. In that moment, I felt a profound connection to the past, as if I were but a fleeting chapter in the epic saga of humanity.The stars twinkled overhead, casting a soft glow upon the sleeping city below. Shadows danced in the flickering lamplight, painting fleeting portraits upon the walls of ancient buildings. I wandered the narrow alleyways, losing myself in the labyrinth of winding streets and hidden courtyards. Each corner held the promise of discovery, a glimpse into a world both familiar and unknown. And as I walked, I couldn't help but wonder what secrets lay hidden beneath the veil of night, waiting to be uncovered by the light of dawn.。

Majestic Pines

Majestic PinesNestled deep within the heart of a lush forest, Majestic Pines stands tall and proud, casting an enchanting shadow over its surroundings. This majestic haven of tranquility is a testament to the beauty of nature and the power it holds to captivate our souls.As you approach Majestic Pines, a sense of awe washes over you. The towering trees reach towards the heavens, their branches stretching outwards as if embracing the sky. The scent of pine fills the air, invigorating your senses and drawing you further into this magical realm.The forest floor beneath your feet is a tapestry of vibrant colors. Soft moss cushions your every step, while delicate wildflowers peek through the undergrowth, adding a touch of whimsy to this picturesque scene. Sunlight filters through the dense canopy above, casting dappled shadows that dance across the forest floor.Birdsong fills the air, a symphony of melodies that serenade your journey through Majestic Pines. The chirping of sparrows, the trilling of thrushes, and the haunting call of the owl create a harmonious chorus that resonates through the trees. It is as if nature itself is singing its praises to this sacred place.As you wander deeper into Majestic Pines, you come across a tranquil stream that meanders through the forest. Its crystal-clear waters glisten in the sunlight, inviting youto dip your toes and immerse yourself in its cool embrace. The gentle babbling of the stream soothes your spirit, washing away the stresses of everyday life.Among the trees, you may encounter some of Majestic Pines' elusive residents. Squirrels scurry playfully along the branches, their fluffy tails trailing behind them. Deer gracefully roam the forest floor, their eyes curious yet cautious. And if you're lucky, you might catch a glimpse of the elusive fox, its fiery red coat blending seamlessly with the autumn foliage.Majestic Pines is not just a place of natural beauty; it also offers a sanctuary for reflection and introspection. The stillness of the forest allows your mind to wander freely, untethered from the distractions of the modern world. Here, you can find solace and reconnect with your inner self, gaining a renewed sense of clarity and purpose.Whether you seek adventure or simply a moment of respite, Majestic Pines has something to offer everyone. Hiking trails wind their way through the forest, leading you to breathtaking vistas and hidden treasures. Picnic areas provide the perfect setting for a leisurely lunch amidst nature's splendor. And for those seeking a more immersive experience, camping grounds offer the opportunity to spend a night under the starry sky, enveloped by the peaceful embrace of Majestic Pines.In a world that often feels chaotic and fast-paced, Majestic Pines stands as a reminder of the inherent beauty and tranquility of nature. It beckons us to slow down, to breathe in the fresh air, and to appreciate the wonders that surround us. Majestic Pines is not just a place; it is an experience that touches the soul and leaves an indelible mark on our hearts.So, let Majestic Pines be your guide as you embark on a journey of discovery and wonder. Allow yourself to be transported to a realm where time slows down, and the beauty of nature reigns supreme. Majestic Pines awaits, ready to unveil its secrets and embrace you in its timeless embrace.。

monkeytrail--汉语资料[整理版]

monkey trail--汉语材料《布特勒法》和“猴子审判”约自1859年达尔文的《物种起源》问世以来，进化论迅速传播到美洲大陆。

众多基督教人士视其为异端邪说，在宗教气氛相对浓厚的南方尤甚。

然而，诅咒和谩骂没能阻止进化论的风行。

20世纪初叶，达尔文的学说进入了美国公立学校的生物学教科书。

反对者们意识到，宗教宣讲和道德谴责已不足以遏制形势的发展，诉诸法律手段也许更为见效。

威廉?詹宁斯?布莱恩（William Jennings Bryan）是当时美国政坛上的传奇人物，3次成为民主党总统候选人，并曾任1913－1915年间的国务卿。

作为一个虔诚的基督徒，布莱恩坚定地认为："进化论是一种没有怜悯心的法则，按照这种法则，强者群起杀死弱者，而《圣经》则是反对进化论的‘爱的法则'"。

1921年，布莱恩发起了"反对在公立学校讲授进化论"运动。

经过四年努力，布赖恩及其追随者获得了成功。

1925年，禁止在公立学校教授"任何否定圣经创世说而代之以人类由低等动物进化而成"的法案被田纳西州议会通过。

这一法案史称《布特勒法》（the Butler law）。

《布特勒法》引起了群情哗然。

成立于1920年的"美国公民自由联盟"（ACLU），一向以保护公民的思想言论自由为宗旨。

ACLU认为，美国公民的基本自由尤其是学术自由应该得到充分的保障，《布特勒法》代表了一种危险的倾向：政府竟然可以根据某种偏见便动用国家的暴力机关来干涉人们研究和传授一种学说的权利，这显然是违宪的。

ACLU决定为那些因教授进化论而被起诉的教师们提供法律上的援助，通过诉讼手段推翻《布特勒法》。

但是，一个奇特的现象出现了。

虽然《布特勒法》规定讲授进化论的公立学校和教师将受到罚款等惩罚，但由于田纳西州州长Austin Peay在签署法案时谨慎地宣布该法案是"象征性法案"，所以该法案实质上并未得到实施，田纳西州的学校、教师还是依旧教授原来的课本。

穿心螺杆英语

穿心螺杆英语Piercing the Heart: The Captivating Journey of the Auger SnailThe auger snail, a captivating creature that dwells in the depths of the ocean, has long been a subject of fascination for marine biologists and enthusiasts alike. These enigmatic mollusks, with their intricate spiral shells and unique hunting strategies, offer a glimpse into the remarkable adaptations that have allowed them to thrive in the underwater realm.At first glance, the auger snail may appear unassuming, but its true allure lies in the intricate details that make it a remarkable predator. Its shell, a testament to the power of evolution, is a masterpiece of engineering, spiraling gracefully in a mesmerizing pattern that has inspired artists and designers throughout history. This architectural marvel not only serves as a protective shield but also plays a crucial role in the snail's hunting prowess.The auger snail's hunting technique is truly awe-inspiring. Unlike many other predatory snails, the auger snail does not rely on brute force or overwhelming numbers to capture its prey. Instead, it employs a unique strategy that combines precision, patience, and aremarkable set of specialized tools. At the heart of this strategy is the snail's radula, a ribbon-like tongue adorned with rows of sharp, harpoon-like teeth.As the auger snail prowls the ocean floor, it uses its radula to meticulously drill through the shells of its prey, often burrowing deep into the vulnerable flesh within. This process, known as "boring," is a marvel of biological engineering, as the snail's radula is perfectly adapted to the task, rotating and flexing with incredible dexterity to penetrate even the most robust of shells.The auger snail's drilling prowess is not the only remarkable aspect of its hunting behavior. These snails also possess a keen sense of chemical detection, allowing them to track their prey with remarkable precision. By detecting the subtle chemical signatures left by their quarry, the auger snail can navigate the vast, murky depths of the ocean with unerring accuracy, homing in on its target with laser-like focus.Once the auger snail has breached its prey's defenses, it injects a potent venom that quickly incapacitates the victim. This venom, a complex cocktail of enzymes and neurotoxins, is a testament to the snail's evolutionary adaptations, allowing it to subdue even the most formidable of prey with remarkable efficiency.The auger snail's hunting prowess is not the only aspect of its biology that has captivated researchers. These snails also possess a remarkable reproductive strategy that is truly unique in the animal kingdom. Unlike many other mollusks, which rely on external fertilization, the auger snail engages in a complex courtship ritual that culminates in internal fertilization.During this process, the male auger snail uses a specialized appendage, known as a penile papilla, to transfer sperm directly to the female's reproductive tract. This intricate mating dance, which can last for hours, is a testament to the snail's sophisticated nervous system and the intricate coordination required to successfully reproduce in the challenging underwater environment.The auger snail's life cycle is also a subject of intense study, as these snails exhibit a remarkable ability to regenerate lost body parts, including their radula and even portions of their intricate shell. This remarkable capacity for regeneration has captured the attention of researchers, who are exploring the potential applications of this ability in fields ranging from medicine to materials science.As we delve deeper into the world of the auger snail, it becomes increasingly clear that these captivating creatures are far more than just another species in the vast ocean ecosystem. They are living embodiments of the incredible adaptations and evolutionarystrategies that have allowed life to thrive in the underwater realm, offering us a window into the incredible diversity and complexity of the natural world.Through the study of the auger snail, we gain a greater appreciation for the intricate web of life that sustains our planet, and the countless wonders that still await discovery in the vast, unexplored depths of the ocean. As we continue to unravel the mysteries of these remarkable mollusks, we are reminded of the importance of preserving and protecting the delicate balance of the marine environment, ensuring that these captivating creatures and countless others like them can continue to captivate and inspire generations to come.。

野性的呼唤英文读后感英文版

野性的呼唤英文读后感英文版野性的呼唤英文读后感英文版（精选11篇）《野性的呼唤》，又名《荒野的呼唤》（The Call of the Wild），美国著名作家杰克伦敦所著。

作品以一只狗的经历表现文明世界的狗在主人的逼迫下回到野蛮，写的是狗，也反映人的世界。

热望本已在，蓬勃脱尘埃；沉沉长眠后，野性重归来。

巴克原是米勒法官家的一只爱犬，经过了文明的教化，一直生活在美国南部加州一个温暖的山谷里。

后被卖到美国北部寒冷偏远、盛产黄金的阿拉斯加，成了一只拉雪橇的狗。

以下是小编为大家带来的野性的呼唤英文读后感英文版，希望大家喜欢。

野性的呼唤英文读后感英文版篇1“When the long winter nights come on and the wolves follow their meat into the lower valleys, he may be seen running at the head of the back through the pale moonlight or glimmering borealis, leaping gigantic above his followers, his great throat a bellow as he sings a song of the younger world, which is the song of the pack.”There was a script about the savage life in the frozen north of ice and snow. There were the unexplored north areas of America and the 19th-century Klondike Gold Rush which dragged men from the entire world into the hard wild to look for gold. There was a road where a gigantic dog like human fought his way to struggle in the wasteland. There was a civilized beast grew from mildness to wildness. And there came the call of the wild.The background and plotIn the 19th century, it was said that gold had been found in the Klondike area in Northern California of vast wilderness, so thousands of people rushed into this uncultivated ground to seekfor gold and fortune, which needed a large quantity of dogs to support for the transportation. There came up Buck story which we can’t define it as luckiness or unluckiness.Buck, a dog weighed one hundred and forty pounds, tall, strong, and heavy muscled, lived a cozy and comfortable life in a rich family of a Judge named Miller, but was soled by evil gardener to two dog dealers and was took to Alaska as a sled dog.Led by his second masters, two governmental couriers, he studied how to pull a sled and how to live in this cruel world where needed more cunning behavior and less fake moral and courtesy. For example, he learned to sleep in the snow hole to get warmness from the clod nights, and he learned to thief bacon and food from his masters and neighboring camps, as well as that, he learned how to fight effectively and efficiently with his antagonists and survive of the combat about the dominant leader with Spitz. In addition to those, he also went through the hardships in the toil on the ice layer, and he learned how to obtain the victory and stand on the wilderness which was beneficial to himself who can only fit the environment, but can’t defy the harness.After the arduous trace and trail, they finally reached the destination, and then, after a short break, dogs including Buck led by a Scotch half-breed man stepped again on the ice land with the Salt Water Mail. It was a hard trip and a monotonous life operating like machine that dogs must undertake the heave pulling and poor condition where they were tired and short of weight. Buck’ partner, Dave who had something wrong inside suffered most of all, but pride as he was, pulling the sled was his holy missionary job which can fulfill his life and must be doneuntil his death. However, the tough work was still continuous.Thirty days passes, by which time Buck and his mates found how really tired and weak they are until they arrived at the last town. They were in a wretched state, worn out and worn out, which was not the tiredness that came from a brief and excessive effort and can be recovered from some hours’ rest, but was the dead tiredness that came through the slow and prolonged strength drainage of months of toil and had to need a long vocation to evacuate. Nevertheless, only three days after they were bought by a family including a foolish woman, a callow and ignorant youngster, and a middle aged man with weak and watery eyes. Never mind of dog’s frazzle, the third masters t ried their best to lash out at them with whip, but Buck was not under very good command and not proud and interested of this career. Until they reached at the camp of Thornton, with the natural instinct and extreme weariness, Buck tolerated the whip from his so called masters and refused to go ahead which was his luckiness to meet his last master, Thornton.Without doubt, Thornton was a good master, full of wisdom, intelligence and love who can manage Buck’s life comfortably and in order. By the careful attendance form his new master, Buck was on his feet quickly and solidly. Filled with the loying love toward his master, Buck companied him, saved his life for several times and helped him win the gambling party. Then, they faced into the East on an unknown trail to achieve where men and dogs as good as themselves has failed, as the call from the wild became stronger and stronger which attracted Buck to leave the civilization to look for. The knife that cut out the bound of Buck between his masters was the mas ter’s deaths which left a void in the dog’s heart and a strengthened calling from the wild.Buck, a civilized dog, finally went back to wolves after thousands of generation by singing a song of the younger world, which is the song of the pack.Survive of the fittestThe Call of the Wild abounded in Darwinism which advocated the evolutionism and natural selection theory.In the process of having to leave the comfortable Miller’s house and adapt to the harsh primitive snowfield, Buck went through the changes from the mildness to wildness where he studied the law of club and fang and admitted the rule of failure without progress. “He had learned well the law of club and fang, and he never forewent an advantage or drew back from a foe he had started on the way t o death.” “He must master or be mastered,” “Kill or be killed, eat or be eaten, was the law; and this mandate, down out of the depths of time, he obeyed.”After analysis, we can find that related to the Darwinism, learning ability was an important factor of the victory of living of Buck. As a south dog living in the rich family and innocent environment, Buck was not wary of Manuel’s uncommon behavior, but situation has changed entirely after a period of barbaric life: he showed hostility to his all possible mates and took precaution of everything. As well as that, throwing away the moral standard and facing the death of starvation, Buck had an ability of thief. “This first theft marked Buck as fit to survive in the hostile Northland environment. It marked his adaptability, his capacity to adjust himself to changing conditions, the lack of which would have meat swift and terrible death.” In addition to those, his muscles became hard as iron, and he grew dumb to all ordinary pain, and he can successful take full use of all the elements no matter internal or external. That’s the progressionof Buck which can equip him with thick helmets from being hurt deeply and made him be the fittest.Not only did he learnt by experience, but instincts long dead became alive again. Maybe knowledge acquired by learning was Buck’s left hand, instincts his right. Good pedigree set up his first sense of a tall, strong and muscular potential king, while the instinct helped him to learn fast and save his life. “It was no task for him to learn to fight with cut and slash and the quick wolf snap.” “They came to him without effort or discovery, as though they had been his always.”Buck changed as his living environment changed. With the change of environment, Buck, compared to the previous southern family dog that was mild and gentle, acquired many abilities and skills. He tried his best to live by becoming cunning, cold-blood, and cruel which make him step forward on the road of corpse and blood. Survive of the fittest which is demonstrated by adaptation to the environment and wielding the law to protect himself and attack on others made him roared on the top of the food chain and return to wolves.All what Buck has done was not due to his reason and thought, but due to his fit. He was fit to everything surrounding him unconsciously and put him to the new way of living quickly.“The theory, ‘Survival of the fittest’, is the law of biological evolution which implies that plants or animals adapt to the environment to survive or to dieit is the biological survival rule of brutal biosphere.” That is to say, the key of this law is that those who can fit the environment can survive, on the contrary, those failed to fit would be obsolete under the rule of elimination.Peeping at Buck and his struggle, we can have a vision of us human that was also fighting in the battlefield with our matesand against our enemy. Filled with bustling stuff, we tried our best to stand on the top of right and authority only because that position would give us more materials and the sense of pride which we depended on to live. Flowers in the greenhouse didn’t know about the hardship of living, so they showed goodwill and send aroma to others; while life in the ice field where wind was blowing like knife and thick snow can bury people only showed a will of survive and cut up the useless goodness to wear on the coldness.We must do it because we had to do it. The pack of animal was like a society of people. Death and genocide would happen on us if we were not willing to fit the environment thoroughly. To dance with the shackle of survive of the fittest was the policy we should carry out forever, the reason why our human stood on the top of biologic chain, and the rule of living of every individual.My opinion on virtue and viceSome people had said virtue was the biggest treasure that human should obey. There is no doubt that kindness, loyalty, honor, love, companionship, sympathy, mercy, and other virtue should be followed. However, I argue that there is transformation between different virtue and even the virtue and vice.Showing the feature of three animals: dog, wolf and human, Buck was the bridge that connected the past and present. As the production of human civilization, dog was evolved from wolf and they would still howl on the wilderness if human didn’t raise and train them.Buck was a mirror from which we can see ourselves. Through this dog, writer told us that only in a place where sun darted its forth beams and everything was in order human will wear the coat of basic goodness, otherwise, kindness would be eliminatedif it met with the club and fang. In the cruel process of primitive accumulation of capitalism, mercy and sympathy was not needed for those quality can lead to death of innocent people. In the period of survive of the fittest, life was not concerned with civilization, while wilderness was the real marrow of life and echoing for the wilderness was the beginning of revival. Buck realized that “Mercy did not exist in the primordial life. It was misunderstood for fear, and such misunderstanding made for death.” This phenomenon can be seen in dogs as well as human. Wilderness were calling for human and eliminating the kindness in human’s heart stealthily.In A Treatise of Human Nature, British philosopher David Hume has said moral came from human’s emotion and conscience but not rationality. The essence of moral existed in the perceptual knowledge, but not rational knowledge. Therefore, the reason why moral distinctions had the division of virtue and vice was that the judgment of moral came from human’s attitude toward their internal actions and external objects. The judgment of moral came from our interest appeal; that is to say, the judgment of moral came from what was good to us, but not what is good.Let us think the question that which direction of Buck’s change to a beast was, progression or retrogression? The answer was that we can’t answer because he survived due to that he threw away those so called virtue and carry out those so called villainy. All what Buck did was under the pressure of living, and he responded to the call of the wild only because he wanted to live. Maybe in the comfortable and civilized Judge’s house, he would stick to the standard of moral and protect the respect of Judge’s riding wh ip by dying under his whip. But in this coldfield, sticking to those so called moral was a fool. Possibly in this kind of world, brutality, cold-bloodedness, cunning and so on was the moral.The division of virtue and vice was the refection of the division of civilization and wilderness to some degree. Maybe we can’t define what moral was and what vice was now in some scene, but we can try to last for enough time to seek for the answer.Run after the free lifeThe call from the wild stood for human’s natur e to run after a simple, independent and free life.Buck was bored of the complex life where he must deal with such a big net of relationship. He just wanted to run and leap through the forest, howled under the grey moonlight, ate what he liked and killed what he liked without many rules to obey. No one desired to live a complicated life for it’s difficult and tiring to reckon other people, while life in the wilderness was just that eat or eaten, kill or killed and there was no middle ground. Easy and simple life was set up on the uncivilized world where creatures didn’t have so much relation and elements to consider. Only being independent from all that can we find what we wanted.When unpracticed Charles and his relatives sunk in a ice hole, writer said th at “A yawning hole was all that was to be seen.” That hole was a capitalistic vast mouth that can eat people, but which would be rotten if we escaped from it. “Here a yellow stream flows from rotted moosehide sacks and sinks into the ground, with long grasses growing through it and vegetable mould overrunning it and hiding its yellow from the sun.” The gold that Thornton got has become a yellow stream because theywere eroded by natural power and lost their value. Imagine in a world where was entirely natural and uncivilized, gold, a kind of iron and currency, was entirely futile, isn’t it?Being free of human world and even free of materials, Buck got a totally new life where he can run at the head of the pack through the pale moonlight to release his vitality and got comfort from nature. We needed materials actually, but material was void actually. How can we get free? To get free of our hearts.ConclusionThere are two sentences I’d like to mention. First, human beings, never degenerate into beasts. Second, beasts, never degenerate into human beings. Correctness of those two sentences should be discussed.Human’s progression began in the point when human beings evolved from wilderness period to civilization, but the retrogression also began at the point when people shared the feast of civilization. For us who are far away from the wilderness and raised and trained by civilization, this book gives us a new vision.Sometimes a picture floating in my mind: in the icy forest, a silhouette of Buck as a wolf caned his neck to howl toward the pale moonlight to echo the howling of pack. That’s the song of animal, and the chant of human, and the snarl of life.野性的呼唤英文读后感英文版篇2The Call of the Wild is London’s most-read book, and generally considered his best, the most masterpiece of his so-called “early period“.The story was set in 19th-century Klondike Gold Rush, in which sled dogs were bought at generous prices.Buck was a domestic dog in Judge Miller’s home and living a comfortable life until he was sold secretly by the poor gardenerand became a sled dog. Buck was a Bernard dog weighed one hundred and forty pounds, tall, strong, and hea一vy muscled. He couldn’t accommodate to the harsh condition at first. And he wanted to fight, to escape, to go back to his cozy home, but in vain.The man in red taught him the law of stick and club-one must first adjust himself to his surroundings and learn the rules, and only after that he can do what he wants to do. The club of the man in red called back Buck’s nature as a dog.When he firstly served for Fran?ois and Perrault, two couriers, he showed his superior ability to adapt to the environment and his smartness to learn everything he wanted to learn. Curly’s death astonished him and taught him to be cautious. And before he had recovered from the shock caused by the tragic passing of Curly, he was harnessed as a sled dog and step by step wanted to be the leader. But the leading dog, Spitz, was already an excellent one, who also considered Buck as enemy and potential competitor. At last, when Spitz once punished him, hurling backward Buck, he knew the time had come. He killed Spitz and took his place.When they pulled into Dawson, Buck was sold as useless thing to three gold diggers, who weren’t veteran in sledding and even didn’t k now how to get to their destination. Food was eaten up half way. So Charles, one of the three, decided to kill Buck when he couldn’t get up. However, when he aimed at Buck, John Thornton sprang upon him, knocked him down and told him that if Charles stroke Buck, Thornton would kill him.Thus, Thornton took Buck away. He was the only true friend of Buck. But Buck was a thing of the wild, especially when the calling of wolf from the hills. Once when he came back from hills,he found that Thornton was killed by Indians. What would you do if you were Buck when your beloved friend was killed? Buck became a nut and killed those headsmen and stayed with Thornton for two days and nights, never lea一ving Thornton out of his sight. And then a nearby wolf howl captures his ears, and he follows the sound to an approaching wolf pack, battling several of these creatures to prove his worth.野性的呼唤英文读后感英文版篇3At the beginning of this century, many new writers emerged with the introduction of many new ideas. Among them, Jack London was the most popular one.His most famous novel is the call of the wild . Although it is a story about a dog, Buck, it vividly depicts the life in the primitive North where people rushed for gold and fortune.Buck, used to belong to a judge, was kidnapped and sold to North. Then he became a member of a dog-team pulling a sled . In the days of pulling a snow-sled, he learned to conform to the law of nature and obey the master. Finally, he found a basic instinct hidden inside him, which enabled himself to survive the tough environment. This is the call of the wild.When you read the story, you will feel that Buck is a man instead of a dog, struggling with his fortune and conforming to the law of nature.Though short, it is really a thrilling story. What you never forget is the tough life in the nature, the brave and crafty dog. Maybe the wild is calling you to go ahead.While writing for only 16 years throughout his life, London produced an amazing body of work among which, White Fang, Martin Eden, the Valley of the Moon are representative.野性的呼唤英文读后感英文版篇4" He sings a song of the younger world, which is the song of the pack." (Chapter VII The Sounding of the Wild) When the last sentence vanished from my eyes, I can still perceive an echo of a song - a wild song, which knocks up my dizzy mind that always cheerfully sink into the so-called civilized world without questioning. Wild, is no longer a symbol of the law of jungle but a headspring where streams out love, passion, bravery, loyalty, friendship, venture, competition and tolerance all these virtues can easily be found in the Call of the Wild.Jack London (1876-1916) is a worldwide renowned novelist. His stories successfully reflect the contradictory views of man’s nature and destiny in and against the wild, and his "fight to survive" notion has gained him and his works timeless popularity, particularly, the Call of the WildIt tells a story of a gigantic dog, named Buck, who is stolen from a rich and comfortable home and forced to learn to survive as an Alaskan sled dog. Buck, at first, is too savage for the company of man until he coincidently encounters his beloved master-kindhearted John Thornton. Finally, John’s incidental death breaks Buck’s last tie to the man and drives him into his long-desired wild with his pack. In the story, Buck and John simply adopt themselves to answer the call of the wild. When it comes to Buck’s mind that one day he will eventually leave John- his master, all he wants to do is just to help him finish the gold-rush-trip. He " from then on, night and day, never put a halt, in desperation, he burst into long stretch of flight, did not to stay him (John)…" (Chapter VII The Sounding of The Wild) Buck wished to remember John’s image forever, he "for two days and nights never left camp, never let Thornton out of his sight. He followed him about at his work, watched him while saw him intoblankets at night and out of them in the morning…" (Chapter VII) When I read these words I just could not hold my tears bursting. Can a real man devote himself to loyalty and friendship in such a way? On the other hand, John Thornton is not only a dog-lover but also a brave and venturous man. He is so straightforward and simple that makes him an accommodating man. Once he firmly roots a goal into his heart, it seems that nothing could prevent him from accomplishing it except death. I do not know whether the persistence is the most vital element to make a man successful, but what I know is that you are not far away from success once you occupy it.It is Jack London who plunges me into the animated wild from the hustle-and-bustle and from desperate city. There, I merely cannot deny the attraction of Buck’s bark, which enlightens me to pursue another lost half of the nature in mankind, and to dig out a true meaning of life. Dare we imagine that London intentionally employs Buck to set us a model with perfect characters (count barbarity out)? The answer is affirmed. We, as animals, are from the wild but shedding off more and more wild signs, which demonstrate us as the "uncivilized". However, who can fully guarantee that we have not overlooked some essential wild-endowed virtues? Especially, nowadays, it seems more crucial for us to stop looking at the post-industrialized world and to ponder for a while. When cheats, betrayals, lies, lusts and crimes stuff a materialized society, whether London uses this novel to help himself escape the reality or warn the earthy people, to us, modern man, is all the same.() It appears horrible that in modern society many people are enthusiastically talking about how to build up "special relations" to the authority, deceiving and lying to each other.To them life is a mask-wearing process rather than a hard work. Every time, you browse WebPages, scandals in politics, business, the entertainment circle and even on campus crowd into your eyes. Oh, what is the essence of human beings? What is the civilization to us? Do we need to look back at where we came from? Is it good or bad for us to speak out what we think and to do what the consciences demand us to? Are we wasting talents given by the mighty nature? Be an honest, straightforward, warmhearted, emotional and responsible man or be a shrewd, cold hearted and astute hypocrite? While embracing the "civilized" rubbish, we are losing those good virtues, which are the calls of the wild. Once we lose them, we are to lose ourselves, and we will get nowhere. I wish this dreadful thought is totally a fallacy, but, now, it is chilling me hard.One day when I happen to stand on the top of a grand mountain to observe a boundless prairie enveloped by the sapphire firmament and combed by gusts of the rhythmical west wind, a morning sun sprinkles me her warmth and brilliance in a graceful way, however, at that moment, I am afraid that I cannot appreciate these beauties, I am a lost " civilized man" then.野性的.呼唤英文读后感英文版篇5The story sounds like just a dog tale at first--a dog, Buck, is kidnapped from his comfortable life in California and sold as a sled dog for the Alaskan gold rush. While he endures the wilderness and the other dogs, Buck learns that survival comes only with tooth and fang. This lesson brings him very close to his forbears, the wolves.If you look deeper, Call of the Wild is as much a story of humans as it is a dog tale. Buck encounters various incompetent masters who try to break his spirit. Are we like this? But Buck alsolearns to trust a master who is gentle and gives love. We can be like this, too.Call of the Wild is not a story for the squeamish or very young. By involving us in the characters lives, Jack London tells the truth. It is a life-and-death war between the harsh land and the soul every day. There is blood, death, cruelty--but its the truth. 野性的呼唤英文读后感英文版篇6Book review: The call of the wildAs a type of novelette, I wasnt used to this cos Ive just finished HarryPotter so in occasions novelette wrote very briefly. The background of the author was very poor, and precisely the time to seek gold. Part of the novel means to expose the hardness of dogs at that time. Men were crazy about gold, the main character, Buck, was stolen by a Gardener of a lawyer who owns Buck.The man with the red sweater taught him the law of clubs, this was a good beginning. The trading road led him at last to two couriers, who knew how to treat dogs. Then the dog team was traded to a three-people family who were seeking good in Alaska. But they didnt know how to treat dogs and at last dogs and men were drowned in the water, except Buck. He was picked up by a man. And eventually Buck was back to the wild-where his ancestors had been.In my opinion a good novel could make readers cry, yell, etc.I clenched my fist when the Family treated the dog team badly, and had a wonderful feeling when the man picked up Buck and treated him like his own son. I t had feeling, this novel…野性的呼唤英文读后感英文版篇7As a dignified individual, survival seems to be the subject of our discussion forever. But in this hard way of survival, the desirefor "life", often let us forget the species. Buck was one of those dogs who worked hard to survive, developed a knack for hardship and eventually became the leader of the pack. But whether it is Barker, or the authors other characters, their hearts are full of longing and yearning for "life". But in this extreme environment and the human strength of the collision, we face the cruelty of competition, witness the true meaning of life.The hero of the novel is a dog named Buck. Set during the Alaskan Gold Rush, the story follows Buck as he climbs from a domesticated Southern dog to a barbarian state in order to survive in the treacherous conditions of the North. Buck is a huge cross dog, he was secretly sold from the family of the south, after several difficulties began to set foot on the road of gold, became a sled working dog, in the cruel domestication process, he realized the justice and the law of nature, the harsh living environment taught him the meaning of cunning and deceit, He took his own cunning and deceit to an unsurpassed level, and after a brutal, even mortal, struggle, he finally established himself as the leader dog. We can get a sense of the mental outlook of different people through the change of owners during the arduous sledding journey. It was in these movements, too, that Buck formed a deep and deep bond with the last master, who had rescued him from the most strenuous drudgery, and whom he had rescued many times. Finally, after the tragic death of his beloved master, he went out into the wilderness, answering the ancient wild call he had heard and yearned for so many times along the way.Buck was only a dog, but his arduous path reflected the true meaning of personal struggle in the age in which the writer lived. It was also a reflection of the naturalism prevalent in Americansociety during the period of the treacherous development of capitalism. On this road, in such a dangerous natural and social environment, only the elite and the strong have the possibility of survival. If they lack the ability to adapt to the changing conditions, it means a quick and tragic death. In front of the laws of nature, man is insignificant and helpless. Moreover, in the struggle for existence, any moral concept becomes "a kind of vanity and an obstacle". On the one hand, this shows the sinister living environment at that time, on the other hand, it also reveals the immoral side of the capitalist society. In such a society, under the action of natural law, the primitive desire, moral decay, the loss of civilization, all show incisively and vividly. Therefore, if survival is the highest goal of human activity, then the process of animal survival is the process of violent meeting and killing each other. Only through the struggle of the law of the jungle, can we ensure the continued survival of the "elite" or "strong" with competitive advantages. Therefore, it fully expresses the authors naturalism thought.The more civilized man is, the more stable his life is, so that in a civilized society things are laid out clearly and there are few accidents. But when something goes wrong, and its serious enough, its the end of the world for those who cant adapt. And Bucks experience also tells us: life is often intense and painful, but in fact it is more full of vitality and vitality and we want to be the strong of life.Thats what survival is all about. There is no justice. Once youre down, youre down. So be careful not to fall. Life on the road, there is no plain sailing, there is no constant, he often changes patterns to teach us to be strong, and we have to do is to accept his arrangement, in perseverance through the cold。

文豪转盘解码 -回复

文豪转盘解码-回复“There is no greater agony than bearing an untold story inside you.”This quote from Maya Angelou resonates deeply with many of us, especially those who feel a compelling need to share their thoughts, experiences, and emotions with the world. Writing allows us to break free from the confines of our minds and express ourselves in ways that can profoundly impact both ourselves and others.Today, let us embark on a literary journey with the 'Literary Roulette,' a decoding game centered around famous writers and their works. This game requires us to decode a series of writings that are represented by a range of authors. By exploring the depths of our own creativity and intellect, we can gain a deeper understanding of the themes, motivations, and messages behind these literary masterpieces.In this article, we will unravel the secret code by taking each author's name as the key to decipher their works. By doing so, we will explore the power of storytelling, the beauty of language, and the universality of human emotions.Our literary journey begins with the enigmatic J.D. Salinger. Salinger's most famous work, 'The Catcher in the Rye,' delves into the mind of Holden Caulfield, a troubled teenager who grapples with alienation, identity, and the loss of innocence. Through Salinger's unique narrative style and Caulfield's introspective monologue, we join Holden on his quest for authenticity and understanding in a world he perceives as full of phoniness. 'The Catcher in the Rye' not only captures the angst of adolescence but also serves as a timeless exploration of the human condition.Moving on to our next stop on this literary journey, we encounter F. Scott Fitzgerald, the mastermind behind 'The Great Gatsby.' Fitzgerald's opus paints a tragic and glittering portrait of the American Dream in the Jazz Age. Set against the backdrop of extravagant parties, unrequited love, and relentless pursuit of wealth, Jay Gatsby serves as a symbol of both the allure and the emptiness that can accompany the relentless pursuit of material success. In 'The Great Gatsby,' Fitzgerald explores themes of illusion, corruption, and the transient nature of happiness, reminding us that the pursuit of dreams can sometimes leave us disillusioned and hollow.Now, let us venture into the Gothic realm with the progenitor of horror-fiction, Edgar Allan Poe. Poe's haunting tales, such as 'The Tell-Tale Heart' and 'The Fall of the House of Usher,' delve into the depths of the human psyche, exploring themes of guilt, fear, and the macabre. Poe's prose embodies a sense of darkness and foreboding, painting vivid pictures of internal anguish and external horrors. Through these stories, Poe reminds us of the fragile boundaries between sanity and madness and the haunting power of the human mind.As we continue our decoding adventure, we encounter the iconic Virginia Woolf. Woolf, an influential figure of the modernist movement, challenges traditional literary conventions and explores the stream of consciousness technique in works like 'Mrs. Dalloway' and 'To the Lighthouse.' By delving into the innermost thoughts and impressions of her characters, Woolf highlights the fragmented nature of human consciousness and the complexities of personal experience. Her intricate use of language and vivid imagery brings characters to life and immerses readers in their inner worlds, encouraging us to question our own perceptions and assumptions about reality.Finally, our journey brings us to the enigmatic Franz Kafka. Kafka's works, such as 'The Metamorphosis' and 'The Trial,' often delve into themes of alienation, bureaucracy, and existential dread. His surreal narratives blur the line between reality and absurdity, highlighting the inherent struggles and futility of the human condition. Kafka's writing forces us to confront our deepest fears and anxieties, provoking introspection while simultaneously making us question the inherent absurdity of our existence.Through this exploration of famous authors and their works, we have deciphered profound insights into the human psyche, society, and the intricacies of the literary craft. We have witnessed the power of storytelling to capture the essence of the human experience and the universality of emotions across time and cultures. Whether it is Salinger's portrayal of teenage angst, Fitzgerald's critique of the American Dream, Poe's exploration of the human mind's darkest corners, Woolf's depiction of the complexities of consciousness, or Kafka's portrayal of existential dread, literature has the power to shed light on the human condition in ways that few other art forms can.So, let us continue on our literary journey, decoding the works ofcountless other authors yet to be explored. For as long as there are untold stories in this world, there will always be a need for writers and readers to come together and allow these stories to be heard. The 'Literary Roulette' serves as a testament to the power of literature to shape our understanding of ourselves and the world around us. So, let us pick up our pens, open our minds, and embark on this never-ending adventure of decoding the untold stories that lie within each of us.。

海底一艘沉船的英文作文

海底一艘沉船的英文作文英文回答：Deep beneath the cerulean waves, where sunlight surrenders to darkness, lies a sunken vessel, a relic of a bygone era. Its once-proud hull, now encrusted with marine life, has become a haunt for enigmatic creatures of the deep.The ship's identity remains shrouded in mystery, its secrets swallowed by the unforgiving sea. Was it a merchant vessel laden with exotic goods, or a warship that met its fate in battle? Perhaps it was an intrepid explorer, venturing into uncharted waters in search of new frontiers. Whatever its purpose, the ship's final resting place is a testament to the indomitable spirit of those who sailed before us.Time has taken its toll on the vessel, its wooden structure slowly being consumed by the relentless tide. Yet,amidst the decay, there lies a haunting beauty, a silent symphony of nature reclaiming what once belonged to man. Marine life has made the wreck its home, creating a vibrant ecosystem that teems with life.Schools of silvery fish dart and gleam through the shadowy interior, their scales shimmering like a thousand tiny mirrors. Sponges, anemones, and other colorful invertebrates cling to the ship's hull, adding splashes of color to the otherwise somber surroundings. Curious crustaceans scuttle across the deck, their antennae twitching with anticipation.The wreck has also become a refuge for larger marine creatures. Giant squid hide within its shadowy depths,their tentacles reaching out to ensnare unsuspecting prey. Curious sharks circle the vessel, their sleek bodies casting ominous silhouettes against the dim light. And occasionally, a majestic whale glides past, its mournful song echoing through the water.For the adventurous diver, exploring the sunken wreckis a thrilling experience. It is a journey into a hidden world, where the past and present intertwine in an enchanting dance. As they navigate the ship's labyrinthine corridors, divers can almost hear the echoes of those who once sailed these waters. They can imagine the laughter and camaraderie of the crew, the tension and excitement of battle, and the silent solitude of a solitary voyage.中文回答：在湛蓝的海浪深处，阳光向黑暗投降的地方，坐落着一艘沉船，这是过去时代的一个遗迹。

专八英语阅读

英语专业八级考试TEM-8阅读理解练习册（1）(英语专业2012级)UNIT 1Text AEvery minute of every day, what ecologist生态学家James Carlton calls a global ―conveyor belt‖, redistributes ocean organisms生物.It’s planetwide biological disruption生物的破坏that scientists have barely begun to understand.Dr. Carlton —an oceanographer at Williams College in Williamstown,Mass.—explains that, at any given moment, ―There are several thousand marine species traveling… in the ballast water of ships.‖ These creatures move from coastal waters where they fit into the local web of life to places where some of them could tear that web apart. This is the larger dimension of the infamous无耻的，邪恶的invasion of fish-destroying, pipe-clogging zebra mussels有斑马纹的贻贝.Such voracious贪婪的invaders at least make their presence known. What concerns Carlton and his fellow marine ecologists is the lack of knowledge about the hundreds of alien invaders that quietly enter coastal waters around the world every day. Many of them probably just die out. Some benignly亲切地，仁慈地—or even beneficially — join the local scene. But some will make trouble.In one sense, this is an old story. Organisms have ridden ships for centuries. They have clung to hulls and come along with cargo. What’s new is the scale and speed of the migrations made possible by the massive volume of ship-ballast water压载水— taken in to provide ship stability—continuously moving around the world…Ships load up with ballast water and its inhabitants in coastal waters of one port and dump the ballast in another port that may be thousands of kilometers away. A single load can run to hundreds of gallons. Some larger ships take on as much as 40 million gallons. The creatures that come along tend to be in their larva free-floating stage. When discharged排出in alien waters they can mature into crabs, jellyfish水母, slugs鼻涕虫，蛞蝓, and many other forms.Since the problem involves coastal species, simply banning ballast dumps in coastal waters would, in theory, solve it. Coastal organisms in ballast water that is flushed into midocean would not survive. Such a ban has worked for North American Inland Waterway. But it would be hard to enforce it worldwide. Heating ballast water or straining it should also halt the species spread. But before any such worldwide regulations were imposed, scientists would need a clearer view of what is going on.The continuous shuffling洗牌of marine organisms has changed the biology of the sea on a global scale. It can have devastating effects as in the case of the American comb jellyfish that recently invaded the Black Sea. It has destroyed that sea’s anchovy鳀鱼fishery by eating anchovy eggs. It may soon spread to western and northern European waters.The maritime nations that created the biological ―conveyor belt‖ should support a coordinated international effort to find out what is going on and what should be done about it. (456 words)1.According to Dr. Carlton, ocean organism‟s are_______.A.being moved to new environmentsB.destroying the planetC.succumbing to the zebra musselD.developing alien characteristics2.Oceanographers海洋学家are concerned because_________.A.their knowledge of this phenomenon is limitedB.they believe the oceans are dyingC.they fear an invasion from outer-spaceD.they have identified thousands of alien webs3.According to marine ecologists, transplanted marinespecies____________.A.may upset the ecosystems of coastal watersB.are all compatible with one anotherC.can only survive in their home watersD.sometimes disrupt shipping lanes4.The identified cause of the problem is_______.A.the rapidity with which larvae matureB. a common practice of the shipping industryC. a centuries old speciesD.the world wide movement of ocean currents5.The article suggests that a solution to the problem__________.A.is unlikely to be identifiedB.must precede further researchC.is hypothetically假设地，假想地easyD.will limit global shippingText BNew …Endangered‟ List Targets Many US RiversIt is hard to think of a major natural resource or pollution issue in North America today that does not affect rivers.Farm chemical runoff残渣, industrial waste, urban storm sewers, sewage treatment, mining, logging, grazing放牧,military bases, residential and business development, hydropower水力发电,loss of wetlands. The list goes on.Legislation like the Clean Water Act and Wild and Scenic Rivers Act have provided some protection, but threats continue.The Environmental Protection Agency (EPA) reported yesterday that an assessment of 642,000 miles of rivers and streams showed 34 percent in less than good condition. In a major study of the Clean Water Act, the Natural Resources Defense Council last fall reported that poison runoff impairs损害more than 125,000 miles of rivers.More recently, the NRDC and Izaak Walton League warned that pollution and loss of wetlands—made worse by last year’s flooding—is degrading恶化the Mississippi River ecosystem.On Tuesday, the conservation group保护组织American Rivers issued its annual list of 10 ―endangered‖ and 20 ―threatened‖ rivers in 32 states, the District of Colombia, and Canada.At the top of the list is the Clarks Fork of the Yellowstone River, whereCanadian mining firms plan to build a 74-acre英亩reservoir水库，蓄水池as part of a gold mine less than three miles from Yellowstone National Park. The reservoir would hold the runoff from the sulfuric acid 硫酸used to extract gold from crushed rock.―In the event this tailings pond failed, the impact to th e greater Yellowstone ecosystem would be cataclysmic大变动的，灾难性的and the damage irreversible不可逆转的.‖ Sen. Max Baucus of Montana, chairman of the Environment and Public Works Committee, wrote to Noranda Minerals Inc., an owner of the ― New World Mine‖.Last fall, an EPA official expressed concern about the mine and its potential impact, especially the plastic-lined storage reservoir. ― I am unaware of any studies evaluating how a tailings pond尾矿池，残渣池could be maintained to ensure its structural integrity forev er,‖ said Stephen Hoffman, chief of the EPA’s Mining Waste Section. ―It is my opinion that underwater disposal of tailings at New World may present a potentially significant threat to human health and the environment.‖The results of an environmental-impact statement, now being drafted by the Forest Service and Montana Department of State Lands, could determine the mine’s future…In its recent proposal to reauthorize the Clean Water Act, the Clinton administration noted ―dramatically improved water quality since 1972,‖ when the act was passed. But it also reported that 30 percent of riverscontinue to be degraded, mainly by silt泥沙and nutrients from farm and urban runoff, combined sewer overflows, and municipal sewage城市污水. Bottom sediments沉积物are contaminated污染in more than 1,000 waterways, the administration reported in releasing its proposal in January. Between 60 and 80 percent of riparian corridors (riverbank lands) have been degraded.As with endangered species and their habitats in forests and deserts, the complexity of ecosystems is seen in rivers and the effects of development----beyond the obvious threats of industrial pollution, municipal waste, and in-stream diversions改道to slake消除the thirst of new communities in dry regions like the Southwes t…While there are many political hurdles障碍ahead, reauthorization of the Clean Water Act this year holds promise for US rivers. Rep. Norm Mineta of California, who chairs the House Committee overseeing the bill, calls it ―probably the most important env ironmental legislation this Congress will enact.‖ (553 words)6.According to the passage, the Clean Water Act______.A.has been ineffectiveB.will definitely be renewedC.has never been evaluatedD.was enacted some 30 years ago7.“Endangered” rivers are _________.A.catalogued annuallyB.less polluted than ―threatened rivers‖C.caused by floodingD.adjacent to large cities8.The “cataclysmic” event referred to in paragraph eight would be__________.A. fortuitous偶然的，意外的B. adventitious外加的，偶然的C. catastrophicD. precarious不稳定的，危险的9. The owners of the New World Mine appear to be______.A. ecologically aware of the impact of miningB. determined to construct a safe tailings pondC. indifferent to the concerns voiced by the EPAD. willing to relocate operations10. The passage conveys the impression that_______.A. Canadians are disinterested in natural resourcesB. private and public environmental groups aboundC. river banks are erodingD. the majority of US rivers are in poor conditionText CA classic series of experiments to determine the effects ofoverpopulation on communities of rats was reported in February of 1962 in an article in Scientific American. The experiments were conducted by a psychologist, John B. Calhoun and his associates. In each of these experiments, an equal number of male and female adult rats were placed in an enclosure and given an adequate supply of food, water, and other necessities. The rat populations were allowed to increase. Calhoun knew from experience approximately how many rats could live in the enclosures without experiencing stress due to overcrowding. He allowed the population to increase to approximately twice this number. Then he stabilized the population by removing offspring that were not dependent on their mothers. He and his associates then carefully observed and recorded behavior in these overpopulated communities. At the end of their experiments, Calhoun and his associates were able to conclude that overcrowding causes a breakdown in the normal social relationships among rats, a kind of social disease. The rats in the experiments did not follow the same patterns of behavior as rats would in a community without overcrowding.The females in the rat population were the most seriously affected by the high population density: They showed deviant异常的maternal behavior; they did not behave as mother rats normally do. In fact, many of the pups幼兽，幼崽, as rat babies are called, died as a result of poor maternal care. For example, mothers sometimes abandoned their pups,and, without their mothers' care, the pups died. Under normal conditions, a mother rat would not leave her pups alone to die. However, the experiments verified that in overpopulated communities, mother rats do not behave normally. Their behavior may be considered pathologically 病理上，病理学地diseased.The dominant males in the rat population were the least affected by overpopulation. Each of these strong males claimed an area of the enclosure as his own. Therefore, these individuals did not experience the overcrowding in the same way as the other rats did. The fact that the dominant males had adequate space in which to live may explain why they were not as seriously affected by overpopulation as the other rats. However, dominant males did behave pathologically at times. Their antisocial behavior consisted of attacks on weaker male,female, and immature rats. This deviant behavior showed that even though the dominant males had enough living space, they too were affected by the general overcrowding in the enclosure.Non-dominant males in the experimental rat communities also exhibited deviant social behavior. Some withdrew completely; they moved very little and ate and drank at times when the other rats were sleeping in order to avoid contact with them. Other non-dominant males were hyperactive; they were much more active than is normal, chasing other rats and fighting each other. This segment of the rat population, likeall the other parts, was affected by the overpopulation.The behavior of the non-dominant males and of the other components of the rat population has parallels in human behavior. People in densely populated areas exhibit deviant behavior similar to that of the rats in Calhoun's experiments. In large urban areas such as New York City, London, Mexican City, and Cairo, there are abandoned children. There are cruel, powerful individuals, both men and women. There are also people who withdraw and people who become hyperactive. The quantity of other forms of social pathology such as murder, rape, and robbery also frequently occur in densely populated human communities. Is the principal cause of these disorders overpopulation? Calhoun’s experiments suggest that it might be. In any case, social scientists and city planners have been influenced by the results of this series of experiments.11. Paragraph l is organized according to__________.A. reasonsB. descriptionC. examplesD. definition12．Calhoun stabilized the rat population_________.A. when it was double the number that could live in the enclosure without stressB. by removing young ratsC. at a constant number of adult rats in the enclosureD. all of the above are correct13.W hich of the following inferences CANNOT be made from theinformation inPara. 1?A. Calhoun's experiment is still considered important today.B. Overpopulation causes pathological behavior in rat populations.C. Stress does not occur in rat communities unless there is overcrowding.D. Calhoun had experimented with rats before.14. Which of the following behavior didn‟t happen in this experiment?A. All the male rats exhibited pathological behavior.B. Mother rats abandoned their pups.C. Female rats showed deviant maternal behavior.D. Mother rats left their rat babies alone.15. The main idea of the paragraph three is that __________.A. dominant males had adequate living spaceB. dominant males were not as seriously affected by overcrowding as the otherratsC. dominant males attacked weaker ratsD. the strongest males are always able to adapt to bad conditionsText DThe first mention of slavery in the statutes法令，法规of the English colonies of North America does not occur until after 1660—some forty years after the importation of the first Black people. Lest we think that existed in fact before it did in law, Oscar and Mary Handlin assure us, that the status of B lack people down to the 1660’s was that of servants. A critique批判of the Handlins’ interpretation of why legal slavery did not appear until the 1660’s suggests that assumptions about the relation between slavery and racial prejudice should be reexamined, and that explanation for the different treatment of Black slaves in North and South America should be expanded.The Handlins explain the appearance of legal slavery by arguing that, during the 1660’s, the position of white servants was improving relative to that of black servants. Thus, the Handlins contend, Black and White servants, heretofore treated alike, each attained a different status. There are, however, important objections to this argument. First, the Handlins cannot adequately demonstrate that t he White servant’s position was improving, during and after the 1660’s; several acts of the Maryland and Virginia legislatures indicate otherwise. Another flaw in the Handlins’ interpretation is their assumption that prior to the establishment of legal slavery there was no discrimination against Black people. It is true that before the 1660’s Black people were rarely called slaves. But this shouldnot overshadow evidence from the 1630’s on that points to racial discrimination without using the term slavery. Such discrimination sometimes stopped short of lifetime servitude or inherited status—the two attributes of true slavery—yet in other cases it included both. The Handlins’ argument excludes the real possibility that Black people in the English colonies were never treated as the equals of White people.The possibility has important ramifications后果，影响.If from the outset Black people were discriminated against, then legal slavery should be viewed as a reflection and an extension of racial prejudice rather than, as many historians including the Handlins have argued, the cause of prejudice. In addition, the existence of discrimination before the advent of legal slavery offers a further explanation for the harsher treatment of Black slaves in North than in South America. Freyre and Tannenbaum have rightly argued that the lack of certain traditions in North America—such as a Roman conception of slavery and a Roman Catholic emphasis on equality— explains why the treatment of Black slaves was more severe there than in the Spanish and Portuguese colonies of South America. But this cannot be the whole explanation since it is merely negative, based only on a lack of something. A more compelling令人信服的explanation is that the early and sometimes extreme racial discrimination in the English colonies helped determine the particular nature of the slavery that followed. (462 words)16. Which of the following is the most logical inference to be drawn from the passage about the effects of “several acts of the Maryland and Virginia legislatures” (Para.2) passed during and after the 1660‟s?A. The acts negatively affected the pre-1660’s position of Black as wellas of White servants.B. The acts had the effect of impairing rather than improving theposition of White servants relative to what it had been before the 1660’s.C. The acts had a different effect on the position of white servants thandid many of the acts passed during this time by the legislatures of other colonies.D. The acts, at the very least, caused the position of White servants toremain no better than it had been before the 1660’s.17. With which of the following statements regarding the status ofBlack people in the English colonies of North America before the 1660‟s would the author be LEAST likely to agree?A. Although black people were not legally considered to be slaves,they were often called slaves.B. Although subject to some discrimination, black people had a higherlegal status than they did after the 1660’s.C. Although sometimes subject to lifetime servitude, black peoplewere not legally considered to be slaves.D. Although often not treated the same as White people, black people,like many white people, possessed the legal status of servants.18. According to the passage, the Handlins have argued which of thefollowing about the relationship between racial prejudice and the institution of legal slavery in the English colonies of North America?A. Racial prejudice and the institution of slavery arose simultaneously.B. Racial prejudice most often the form of the imposition of inheritedstatus, one of the attributes of slavery.C. The source of racial prejudice was the institution of slavery.D. Because of the influence of the Roman Catholic Church, racialprejudice sometimes did not result in slavery.19. The passage suggests that the existence of a Roman conception ofslavery in Spanish and Portuguese colonies had the effect of _________.A. extending rather than causing racial prejudice in these coloniesB. hastening the legalization of slavery in these colonies.C. mitigating some of the conditions of slavery for black people in these coloniesD. delaying the introduction of slavery into the English colonies20. The author considers the explanation put forward by Freyre andTannenbaum for the treatment accorded B lack slaves in the English colonies of North America to be _____________.A. ambitious but misguidedB. valid有根据的but limitedC. popular but suspectD. anachronistic过时的，时代错误的and controversialUNIT 2Text AThe sea lay like an unbroken mirror all around the pine-girt, lonely shores of Orr’s Island. Tall, kingly spruce s wore their regal王室的crowns of cones high in air, sparkling with diamonds of clear exuded gum流出的树胶; vast old hemlocks铁杉of primeval原始的growth stood darkling in their forest shadows, their branches hung with long hoary moss久远的青苔;while feathery larches羽毛般的落叶松,turned to brilliant gold by autumn frosts, lighted up the darker shadows of the evergreens. It was one of those hazy朦胧的, calm, dissolving days of Indian summer, when everything is so quiet that the fainest kiss of the wave on the beach can be heard, and white clouds seem to faint into the blue of the sky, and soft swathing一长条bands of violet vapor make all earth look dreamy, and give to the sharp, clear-cut outlines of the northern landscape all those mysteries of light and shade which impart such tenderness to Italian scenery.The funeral was over,--- the tread鞋底的花纹/ 踏of many feet, bearing the heavy burden of two broken lives, had been to the lonely graveyard, and had come back again,--- each footstep lighter and more unconstrained不受拘束的as each one went his way from the great old tragedy of Death to the common cheerful of Life.The solemn black clock stood swaying with its eternal ―tick-tock, tick-tock,‖ in the kitchen of the brown house on Orr’s Island. There was there that sense of a stillness that can be felt,---such as settles down on a dwelling住处when any of its inmates have passed through its doors for the last time, to go whence they shall not return. The best room was shut up and darkened, with only so much light as could fall through a little heart-shaped hole in the window-shutter,---for except on solemn visits, or prayer-meetings or weddings, or funerals, that room formed no part of the daily family scenery.The kitchen was clean and ample, hearth灶台, and oven on one side, and rows of old-fashioned splint-bottomed chairs against the wall. A table scoured to snowy whiteness, and a little work-stand whereon lay the Bible, the Missionary Herald, and the Weekly Christian Mirror, before named, formed the principal furniture. One feature, however, must not be forgotten, ---a great sea-chest水手用的储物箱,which had been the companion of Zephaniah through all the countries of the earth. Old, and battered破旧的，磨损的, and unsightly难看的it looked, yet report said that there was good store within which men for the most part respect more than anything else; and, indeed it proved often when a deed of grace was to be done--- when a woman was suddenly made a widow in a coast gale大风，狂风, or a fishing-smack小渔船was run down in the fogs off the banks, leaving in some neighboring cottage a family of orphans,---in all such cases, the opening of this sea-chest was an event of good omen 预兆to the bereaved丧亲者;for Zephaniah had a large heart and a large hand, and was apt有…的倾向to take it out full of silver dollars when once it went in. So the ark of the covenant约柜could not have been looked on with more reverence崇敬than the neighbours usually showed to Captain Pennel’s sea-chest.1. The author describes Orr‟s Island in a(n)______way.A.emotionally appealing, imaginativeB.rational, logically preciseC.factually detailed, objectiveD.vague, uncertain2.According to the passage, the “best room”_____.A.has its many windows boarded upB.has had the furniture removedC.is used only on formal and ceremonious occasionsD.is the busiest room in the house3.From the description of the kitchen we can infer that thehouse belongs to people who_____.A.never have guestsB.like modern appliancesC.are probably religiousD.dislike housework4.The passage implies that_______.A.few people attended the funeralB.fishing is a secure vocationC.the island is densely populatedD.the house belonged to the deceased5.From the description of Zephaniah we can see thathe_________.A.was physically a very big manB.preferred the lonely life of a sailorC.always stayed at homeD.was frugal and saved a lotText BBasic to any understanding of Canada in the 20 years after the Second World War is the country' s impressive population growth. For every three Canadians in 1945, there were over five in 1966. In September 1966 Canada's population passed the 20 million mark. Most of this surging growth came from natural increase. The depression of the 1930s and the war had held back marriages, and the catching-up process began after 1945. The baby boom continued through the decade of the 1950s, producing a population increase of nearly fifteen percent in the five years from 1951 to 1956. This rate of increase had been exceeded only once before in Canada's history, in the decade before 1911 when the prairies were being settled. Undoubtedly, the good economic conditions of the 1950s supported a growth in the population, but the expansion also derived from a trend toward earlier marriages and an increase in the average size of families; In 1957 the Canadian birth rate stood at 28 per thousand, one of the highest in the world. After the peak year of 1957, thebirth rate in Canada began to decline. It continued falling until in 1966 it stood at the lowest level in 25 years. Partly this decline reflected the low level of births during the depression and the war, but it was also caused by changes in Canadian society. Young people were staying at school longer, more women were working; young married couples were buying automobiles or houses before starting families; rising living standards were cutting down the size of families. It appeared that Canada was once more falling in step with the trend toward smaller families that had occurred all through theWestern world since the time of the Industrial Revolution. Although the growth in Canada’s population had slowed down by 1966 (the cent), another increase in the first half of the 1960s was only nine percent), another large population wave was coming over the horizon. It would be composed of the children of the children who were born during the period of the high birth rate prior to 1957.6. What does the passage mainly discuss?A. Educational changes in Canadian society.B. Canada during the Second World War.C. Population trends in postwar Canada.D. Standards of living in Canada.7. According to the passage, when did Canada's baby boom begin?A. In the decade after 1911.B. After 1945.C. During the depression of the 1930s.D. In 1966.8. The author suggests that in Canada during the 1950s____________.A. the urban population decreased rapidlyB. fewer people marriedC. economic conditions were poorD. the birth rate was very high9. When was the birth rate in Canada at its lowest postwar level?A. 1966.B. 1957.C. 1956.D. 1951.10. The author mentions all of the following as causes of declines inpopulation growth after 1957 EXCEPT_________________.A. people being better educatedB. people getting married earlierC. better standards of livingD. couples buying houses11.I t can be inferred from the passage that before the IndustrialRevolution_______________.A. families were largerB. population statistics were unreliableC. the population grew steadilyD. economic conditions were badText CI was just a boy when my father brought me to Harlem for the first time, almost 50 years ago. We stayed at the hotel Theresa, a grand brick structure at 125th Street and Seventh avenue. Once, in the hotel restaurant, my father pointed out Joe Louis. He even got Mr. Brown, the hotel manager, to introduce me to him, a bit punchy强力的but still champ焦急as fast as I was concerned.Much has changed since then. Business and real estate are booming. Some say a new renaissance is under way. Others decry责难what they see as outside forces running roughshod肆意践踏over the old Harlem. New York meant Harlem to me, and as a young man I visited it whenever I could. But many of my old haunts are gone. The Theresa shut down in 1966. National chains that once ignored Harlem now anticipate yuppie money and want pieces of this prime Manhattan real estate. So here I am on a hot August afternoon, sitting in a Starbucks that two years ago opened a block away from the Theresa, snatching抓取，攫取at memories between sips of high-priced coffee. I am about to open up a piece of the old Harlem---the New York Amsterdam News---when a tourist。

印度七叶树英文作文

印度七叶树英文作文Amidst the rich tapestry of India's biodiversity, the Ashoka tree, known scientifically as Saraca indica, stands tall with a storied legacy that transcends the bounds of mere botany. Its significance extends to the very fabric of Indian culture, history, and religion, making it a symbolof both national pride and spiritual enlightenment.The Ashoka tree is a deciduous species, characterizedby its distinctive seven-lobed leaves that fluttergracefully in the breeze, hence its common name. These leaves, often used in traditional Indian medicine, are believed to possess healing properties. The tree's bark, too, is valued for its medicinal qualities, while its flowers, which bloom in clusters, attract a myriad of pollinators and add a burst of color to the Indian landscape.However, the Ashoka's significance goes beyond its physical attributes. It is a symbol of peace and prosperity, a testament to the ancient Indian emperor Ashoka's conversion to Buddhism and his subsequent efforts to spread the teachings of compassion and non-violence across hisvast empire. Ashoka's edicts, inscribed on pillars and stones throughout his realm, often featured the Ashoka tree as a symbol of his newfound faith and philosophy.The Ashoka tree also holds a place of reverence in Hindu mythology. Legends associate the tree with Lord Krishna, who is said to have rested under its shady branches during his lifetime. Hindus often visit Ashoka groves during festivals and pilgrimages, seeking solace and spiritual enlightenment.In modern India, the Ashoka tree remains a national symbol, often depicted in official emblems and stamps. Its presence in cities and villages alike serves as a reminder of India's rich cultural heritage and the country's commitment to environmental conservation.The Ashoka tree, with its seven-lobed leaves and deep cultural roots, is a powerful symbol of India's unity in diversity. It stands as a testament to the harmonious coexistence of different faiths and cultures within the Indian subcontinent, and as a reminder of the country'srich historical and spiritual legacy.**迷人的印度七叶树**在印度生物多样性的丰富画卷中，七叶树，科学名称为Saraca indica，以其独特的故事传统而高耸入云，超越了纯粹植物学的范畴。

《老人与海》英文读后感

《老人与海》英文读后感The Old Man and the Sea is a novel written by American author Ernest Hemingway, published in 1952. The story revolves around an elderly fisherman, Santiago, who has not caught any fish in 84 days. The novel portrays Santiago's struggle against the elements of nature and society to catch a large marlin.First and foremost, the novel is a poignant commentary on the human condition. It shows that no matter how skilled or experienced one may be, they can still face adversity that tests their resilience and determination. Santiago represents what it means to be human – someone who is determined to achieve their goals, but also vulnerable to the trials of life.The novel also explores themes of isolation and loneliness. Santiago lives in a community where fishermen are judged by their ability to catch fish, but he is isolated from his fellow fishermen due to his lack of success in recent months. Despite this, Santiago remains steadfast in his pursuit of a large fish, even if it means battling against the elements on his own.Furthermore, the novel is an insightful look into the relationship between man and nature. Hemingway depicts the ocean as a powerful force, and Santiago as a humble fisherman in the face of the vast expanse of water. Santiago's respect for the marlin he catches symbolizes the interconnectedness between man and nature, and the message that we must care for and protect the environment around us.Hemingway's writing style is also noteworthy in this novel. His useof short, simple sentences and minimalist prose effectively conveys the struggle and intensity of Santiago's experience. The language is direct and evocative, providing a vivid description of Santiago's journey and the oceanic landscape that surrounds him. In conclusion, The Old Man and the Sea is a beautiful and engaging novel that delves into the complexities of human nature and the relationship between man and nature. Hemingway's writing style effectively captures the essence of the story, making it both a challenging and rewarding read. This novel is a timeless classic that continues to inspire readers of all ages and backgrounds, and it is highly recommended for anyone looking for a thought-provoking and emotional story.。

关于猴子的作文英语

Monkeys are fascinating creatures that have captured the imagination of humans for centuries.They are known for their intelligence,agility,and playful behavior.Heres a detailed essay on monkeys,exploring their characteristics,habitats,and the role they play in various cultures.IntroductionMonkeys are primates,a group of mammals that also includes humans,apes,and prosimians.They are found in various parts of the world,from the dense jungles of South America to the arid regions of Africa.Monkeys are known for their social behavior,with many species living in large groups known as troops.They are also highly adaptable, being able to thrive in a variety of environments.Physical CharacteristicsMonkeys come in a wide range of sizes and shapes.The smallest species,such as the pygmy marmoset,is no larger than a human thumb,while the largest,like the mandrill, can weigh up to35kilograms.They typically have long tails,which they use for balance and as a fifth limb when climbing trees.Monkeys have opposable thumbs,which allow them to grasp objects with precision,a trait that has contributed to their dexterity and ability to manipulate their environment.HabitatsMonkeys can be found in a variety of habitats,including tropical rainforests,savannas, and mountainous regions.They are arboreal creatures,meaning they spend most of their time in trees.This lifestyle has led to the evolution of several adaptations,such as prehensile tails that can be used to grasp branches.In some species,like the capuchin monkey,these tails are almost as long as their bodies.DietThe diet of monkeys varies depending on the species and their habitat.Some are herbivores,feeding primarily on fruits,leaves,and flowers,while others are omnivores, consuming a mix of plant and animal matter.Monkeys are known for their love of fruit, which provides them with the necessary nutrients and energy for their active lifestyles. They also play a crucial role in seed dispersal,helping to maintain the health of their forest ecosystems.Social BehaviorMonkeys are highly social animals,often living in groups that can range from a dozen to several hundred individuals.These troops are organized with a strict hierarchy,with a dominant male,or alpha,leading the group.Social bonds among monkeys are strong,and they communicate with each other using a variety of vocalizations,facial expressions, and body language.Grooming is a common activity among monkeys,serving not only to clean each other but also to reinforce social bonds.Reproduction and ParentingMost monkey species have a gestation period of about six months,after which the female gives birth to a single offspring,or occasionally twins.The young are highly dependent on their mothers for the first few months of life,clinging to their mothers fur as they are carried around.Males do not typically participate in the rearing of young,but the entire troop will often rally to protect the vulnerable infants.Cultural SignificanceMonkeys have been revered and depicted in the art and mythology of many cultures.In Hinduism,the monkey god Hanuman is a central figure,symbolizing strength,devotion, and the power of good over evil.In Chinese culture,the Monkey King is a beloved character from the classic novel Journey to the West,embodying wit,courage,and a rebellious spirit.Monkeys are also featured in various folktales and proverbs,often representing cleverness and resourcefulness.ConservationUnfortunately,many monkey species are threatened by habitat loss,poaching,and the illegal pet trade.Deforestation,in particular,has led to a significant decline in the populations of arboreal monkeys.Conservation efforts are underway to protect these species and their habitats,including the establishment of protected areas and the implementation of antipoaching measures.ConclusionMonkeys are an integral part of our planets biodiversity,contributing to the health of ecosystems and the cultural richness of human societies.Their playful antics and social behaviors not only provide us with a window into the lives of these intelligent creatures but also serve as a reminder of our own primate heritage.As we continue to learn moreabout these fascinating animals,it is crucial that we work to protect them and the habitats they call home.。

欧内斯特沙克尔顿坚忍号英语作文

欧内斯特沙克尔顿坚忍号英语作文Ernest Shackleton and the Endurance ExpeditionErnest Shackleton was a renowned British explorer who led the famous Endurance expedition to Antarctica in the early20th century. The goal of the expedition was to make thefirst land crossing of the Antarctic continent, a feat that had eluded explorers for centuries. However, the journey turned into a struggle for survival when their ship, the Endurance, became trapped in the ice and eventually sank.Shackleton and his crew of 27 men were stranded on the ice for over a year, enduring harsh conditions and constant danger. Shackleton showed incredible leadership and determination in the face of adversity, keeping his men motivated and focused on the goal of survival. He famously declared, "For scientific leadership, give me Scott; forswift and efficient travel, Amundsen; but when you are in ahopeless situation, when there seems to be no way out, get on your knees and pray for Shackleton."After the Endurance sank, Shackleton and his crew set out on a daring journey to reach safety. They traveled across the ice in lifeboats, facing freezing temperatures and treacherous ice floes. Finally, after a grueling 800-mile journey, they reached the inhabited island of South Georgia, where they were able to summon help and rescue the rest of their crew.Shackleton's leadership and courage during the Endurance expedition have made it one of the most famous stories of adventure and survival in history. His ability to keep his men focused and hopeful in the face of almost impossible odds is a testament to his extraordinary character. Shackleton's determination and resilience continue to inspire people around the world to this day.In conclusion, Ernest Shackleton's leadership during the Endurance expedition is a remarkable example of human endurance and bravery. His ability to keep his crew motivated and focused on survival in the most desperate of circumstances is a testament to the power of leadership and determination. Shackleton's legacy as one of the greatest explorers of all time continues to inspire generations of adventurers and leaders.。

善心感动天地的英语作文

In the heart of every community lies an unsung hero,a person whose acts of kindness and compassion are so profound that they touch the very essence of humanity. This essay narrates the story of such an individual,whose selfless deeds have not only inspired those around them but also moved the heavens and the earth.In a small,quaint village nestled in the heart of the countryside,there lived a humble farmer named Thomas.His life was simple,revolving around the rhythm of the seasons and the nurturing of the land.Yet,it was his heart that was truly bountiful,always ready to lend a helping hand to those in need.One fateful day,as the village was ravaged by a severe drought,the crops withered,and the villagers were on the brink of despair.It was then that Thomas decided to take matters into his own hands.He sold his only valuable possession,a prized bull that had been in his family for generations,to buy water for the entire village.His selfless act was a beacon of hope in the midst of adversity.Word of Thomass generosity spread far and wide,and soon,people from neighboring villages and even distant towns began to take notice.Inspired by his actions,they too started contributing to the cause,pooling resources to alleviate the suffering of the droughtstricken community.As the weeks passed,the heavens seemed to respond to the collective outpouring of goodwill.The skies opened up,and a gentle rain began to fall,nourishing the parched earth and bringing life back to the withered crops.It was as if the very elements had been moved by the kindness and selflessness of one mans heart.Thomass story is a testament to the power of compassion and the profound impact that a single act of kindness can have.It serves as a reminder that even in the face of overwhelming odds,the human spirit can triumph through love,generosity,and the unwavering belief in the goodness of others.In conclusion,the tale of Thomas and his extraordinary act of kindness is a beacon of hope in a world that often seems consumed by selfinterest and greed.It is a story that will continue to inspire generations to come,a story of how one persons selfless deed can indeed move the heavens and the earth.。

传说中的一百句背七千单词

传说中的100句背7000单词1. Typical of the grassland dwellers of the continent is the American antelope, or pronghorn.1.美洲羚羊，或称叉角羚，是该大陆典型的草原动物。

2. Of the millions who saw Haley's comet in 1986, how many people will live long enough to see it return in the twenty-first century.2. 1986年看见哈雷慧星的千百万人当中，有多少人能够长寿到足以目睹它在二十一世纪的回归呢？3. Anthropologists have discovered that fear, happiness, sadness, and surprise are universally reflected in facial expressions.3.人类学家们已经发现，恐惧，快乐，悲伤和惊奇都会行之于色，这在全人类是共通的。

4. Because of its irritating effect on humans, the use of phenol as a general antiseptic has been largely discontinued.4.由于苯酚对人体带有刺激性作用，它基本上已不再被当作常用的防腐剂了。

5. In group to remain in existence, a profit-making organization must, in the long run, produce something consumers consider useful or desirable.5.任何盈利组织若要生存，最终都必须生产出消费者可用或需要的产品。

山鸟与鱼的英语作文

The mountain bird and the fish share a unique bond, a story of coexistence and mutual understanding that transcends their natural habitats. In the tranquility of the forest, the mountain bird, with its vibrant feathers and melodious song, is a symbol of freedom and joy. It soars through the skies, exploring the vast expanse of nature, and finds solace in the branches of trees that provide it a home.Meanwhile, the fish, a creature of the deep, navigates the silent depths of the rivers and lakes. Its scales glisten under the waters surface, reflecting the play of light that filters through the water. The fish is a symbol of adaptability and resilience, thriving in an environment that is as mysterious as it is beautiful.Despite their different worlds, the mountain bird and the fish share a common thread. They both embody the essence of life in their respective elements. The bird, with its ability to fly, represents the aspiration to reach new heights and explore the unknown. The fish, with its grace in the water, symbolizes the importance of staying connected to ones roots and adapting to ones surroundings.Their relationship is a testament to the interconnectedness of all living beings. The bird, while perched on a branch overhanging the water, might observe the fish swimming below, and the fish, in turn, might look up to see the birds silhouette against the sky. In these moments of silent observation, they acknowledge each others presence, recognizing the beauty and value of their distinct lives.The story of the mountain bird and the fish is a reminder that even in a world filled with diversity, there is a shared sense of harmony and balance. It encourages us to appreciate the differences among us and to find unity in our diversity. Just as the bird and the fish coexist in their own unique ways, we too can learn to live in harmony, respecting and celebrating the distinct qualities that each of us brings to the world.In conclusion, the tale of the mountain bird and the fish is a poignant narrative that speaks to the heart of our existence. It is a story that transcends the boundaries of language and culture, reminding us of the simple yet profound truth that we are all part of the same living tapestry, each with our own role to play in the grand scheme of life.。

英语作文我最敬佩的军人

The soldier I admire the most is not a figure from history books or a character from a movie he is a real person who has shown me the true meaning of courage and dedication. His name is Captain James, and he is a friend of my fathers.Captain James has served in the military for over a decade, and during that time, he has been deployed to various parts of the world on numerous missions. What makes him stand out is not just his bravery in the face of danger, but also his unwavering commitment to his fellow soldiers and the values he holds dear.One of the most striking aspects of Captain James character is his selflessness. He has been known to put the needs of others before his own on multiple occasions. There was a time when his unit was trapped in a hostile environment, and he took the lead to ensure everyones safety, even at the risk of his own life. His actions that day saved many lives, and it was a testament to his courage and leadership.Another quality that I admire in Captain James is his resilience. He has faced many challenges and hardships throughout his military career, but he has never let them break his spirit. Instead, he uses these experiences to grow stronger and become a better soldier and leader.Captain James is also a person of great integrity. He always stands up for what he believes is right, even when it is not the popular opinion. This has earned him the respect of his peers and superiors, as well as the trust of those under his command.In addition to his military accomplishments, Captain James is also a mentor to many young soldiers. He takes the time to teach them not only about the skills they need to succeed in the military but also about the importance of character and values. His guidance has had a profound impact on the lives of many, and it is a testament to his commitment to the wellbeing of others.In conclusion, Captain James is the soldier I admire the most because of his courage, selflessness, resilience, and integrity. He is a true hero who embodies the best qualities of a military leader and a human being. His actions and dedication serve as an inspiration to me and many others, and I am grateful for the opportunity to know him and learn from his example.。

词汇正

词汇10000第一课纪念碑是为了纪念胜利而建的。

孩子们挤成一团取暖。

责难有时比惩罚更难以承受。

新疫苗在疾病的所有痕迹三个月。

这群野蛮人玷污了这所教堂,把它当做马厩。

孕妇的肚子越来越大。

迷失方向的徒步旅行者丧失了所有希望,当营救飞机没有发现他们。

孩子丧亲就是由于他们的父母亲死了。

这场战场被视为圣地以纪念战死在这里的战士。

真正的笑话不一定能激起一阵狂笑。

左车轮陷在泥泞路上。

那辆旧车,将乘客剧烈的摇晃在崎岖的路上。

向女士鞠躬致敬已经是一种过时的习惯。

许多野生动物在夜间觅食找东西吃。

孩子们在沙滩上挖洞。

外交官们关注世界事务的情势。

农民控告火车站由于他的牛被火车。

水槽的台面上有许多凹槽,水走。

那只猫在地窖里徘徊寻找老鼠。

我们都同情丈夫,他丧失了他心爱的妻子。

她的歌声博得了公众的钦佩。

我们仍然用这台机器尽管它已经陈旧。

典型的西方电影里强盗的骑着马并配armed.单独或一组。

圣诞节是纪念耶稣基督的诞生。

孩子们泥泞的鞋子污染了旅馆的地毯。

在礼堂里奔跑违反了学校的纪律的,也是不允许的。

她能忍受他人的令人失望的地方可容忍的坚韧。

这个小女孩悲痛欲绝失去了她的小猫。

你不饿吗?你只吃了一丁点东西。

新国王的加冕典礼是一个非常壮丽的场面。

水灾之后,通常瘟疫会接踵而来的疾病。

那个残疾的孩子从楼梯上摔下来了,伤得很重。

船上的铁引起了偏差磁式指南针的。

马拉松选手必须具有很好的耐力才能跑那么长的距离。

这个美丽的女孩的名声被恶毒的流言玷污了。

这个小男孩刚开始学走路,他经常摔倒在地板上。

新主席的就职典礼的开始是一个非常壮丽的场面。

有许多疾病困扰着老人。

他的老板责难他轻视工作。

小偷闯房子谨慎地伪装着闯进房间。

如今,是一种不人道的惩罚违抗命令的士兵或鞭打的水手。

根据基石上的题字,这座房子建于1919年。

慈善礼物干扰一个人的私人事务。

他没有坐直,他的姿势很糟糕。

约翰翻遍了所有的抽屉寻找他的手套。

水管道都喯出来了。

登山者跨越了一条很长的水平裂缝山坡正面。

考研英语重点词汇详解holy

考研英语重点词汇详解holyholy英[ˈhəʊli]美[ˈhoʊli]adj.献身于上帝的；尊崇上帝的；神圣的；哎呀；糟糕；圣洁的；虔诚的；道德和精神卓越的比较级：holier最高级：holiest英文释义：1.[usually before noun] connected with God or a particular religion【通常在名词前】与上帝或者特定的宗教有关2. good in a moral and religious way以道德和宗教的方式行善3. [only before noun] (informal) used to emphasize that you are surprised, afraid【仅在名词前】(非正式)用来强调你感到惊讶、害怕举个例子：1.A holy person is required to read the Holy Bible.圣徒必读《圣经》。

2.The priest sprinkled the baby with holy water.牧师往那孩子身上洒圣水。

3.The boss invited me into his holy of holies this morning. Whata fantastic office he’s got!今早老板邀我去他的圣地—他的办公室真是太棒了！4.He is a holy Buddhist.他是一个虔诚的佛教徒。

5.To them, as to all Poles, this is a holy place. (15KB)正如对所有的极地人一样，对他们来说，这里是个神圣的地方。

常用短语：holy spirit [宗]圣灵（等于Holy Ghost）holy ghost n. [宗]圣灵holy place n. 圣所；圣殿holy one n. 神；上帝holy land n. （基督教）圣地（指巴勒斯坦）holy grail 圣杯；圣盘holy bible n. 圣经holy mountain 魂山，圣山holy father 基督教圣父（指上帝）；天主教徒对罗马教皇的尊称holy roman empire n. 神圣罗马帝国holy see [宗]圣座；罗马教廷；宗座holy war 圣战；网络上因基本观点不同产生的激烈争论holy trinity 三位一体（基督教圣父，圣子，圣灵三位一体）holy man 圣人，神职人员holy communion [宗]圣餐holy week 圣周（复活节前的一周）holy day 宗教节日holy family 圣家庭（指圣婴耶稣、圣母玛利亚、圣约瑟等）holy scripture 圣经holy cow [俚]不会吧！；哎呀！；我的天啊（等于holy cats）词汇拓展：近义词n. topographic point, place, spotadj. beatified, blessed, Blessed, consecrated, sacred, sanctified, hallowed反义词n. unholy, unhallowed联想词sacred神圣的;trinity三位一体;unholy不神圣的;pious虔诚的;divine神圣的; righteous公正的; profane世俗的; sanctity圣洁;shrine圣地; pilgrimage朝圣者的旅程; saint圣徒;long-standing英[ˌlɒŋˈstandɪŋ]美[ˈlɔŋˈˌstændɪŋ] adj.长期存在的；长期持续的英文释义：that has existed or lasted for a long time已经存在或者持续了很长时间的举个例子：1.The Church's long-standing dogma was losing the great battle for the truth to rationalists and scientists. (31KB)在这场为真理而战的伟大斗争中，存在已久的教会教条输给了理性主义者和科学家。

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a r X i v :h e p -p h /9510282v 1 12 O c t 1995String junction as a baryonic constituentYu.S.Kalashnikova ∗,A.V.Nefediev †Institute of Theoretical and Experimental Physics117259,Moscow,RussiaAbstractWe extend the model for QCD string with quarks to consider the Mercedes Benz string conﬁguration describing the three-quark baryon.Under the assumption of adiabatic separation of quark and string junction motion we formulate and solve the classical equation of motion for the junction.We dare to quantize the motion of the junction,and discuss the impact of these modes on the baryon spectra.The qqq baryon,together with the q ¯q meson,is usually considered in the framework of the constituent model as a simplest system with zero triality.It is clear,nevertheless,that in the QCD -motivated approach the only way to form gauge-invariant states with three quarks in the fundamental colour representation is to introduce the so-called string junction as an object that couples three quarks to make a colour singlet:Ψ(x 1x 2x 3,x 0)==ψα(x 1)ψβ(x 2)ψγ(x 3)Φα′α(x 0,x 1)Φβ′β(x 0,x 2)Φγ′γ(x 0,x 3)εα′β′γ′,(1)where parallel transporters Φ,Φαβ(x,y )=(P exp igx yB a µt adz µ)αβ,(2)stand to assure non-local gauge invariance of the qqq system placed into non-trivial QCDbackground B aµ.From this point of view it is obvious that the baryon should be treated as a simplest multiquark system containing,in comparison to the q ¯q system,a new object with it’s own dynamics.Standard way to deal with the junction dynamics is to assume that it always moves in such a way that the sum of distances between quarks and junc-tion is minimal [1,2].This assumption is motivated by non-relativistic approach,where conﬁnement manifests itself as linear potential between constituents.On the other hand,the idea that a junction might be responsible for certain kinds of baryonic excitations was already discussed in [2].In the present letter we relax the above-mentioned assumption on a junction following submissively the quarks.Actually our baryon is going to contain four constituents rather than three.Our starting point is the Vacuum Background Correlators method[3].In the framework of this method the hadronic Green functions can be constructed starting from the QCD Lagrangian.The dynamics of interaction is deﬁned by the averages of Wilson loop operators,and it may be shown that the area law asymptotic for Wilson loop average gives rise to the string-type interaction of the constituents.The model for the resulting straight-line q¯q string was considered in[4],and the hybrid mesonic excitations were analysed in[5].To formulate the Hamiltonian approach to the problem one is to consider the Green function of a baryon,G(x1x2x3x0,y1y2y3y0)=<Ψ(x1x2x3,x0)|Ψ(y1y2y3,y0)>B,(3) where the brackets mean the averaging over backgroundﬁeld conﬁgurations.To deﬁne the eﬀective action the Feynman-Schwinger representation[6]of a Green function(3)is used(in the Euclidean space):G(x1x2x3x0,y1y2y3y0)= ∞0ds1 ∞0ds2 ∞0ds3 Dz1Dz2Dz3××exp(−K)·<W>B(4) whereW=εαβγΦαα′(Γ1)Φββ′(Γ2)Φγγ′(Γ3)εα′β′γ′K=3 i=1(m2q i s i+13!εα1α2α3εβ1β2β3Φα1β1(Γ)Φα2β2(Γ)Φα3β3(Γ)(5)(which is due to the unimodularity condition for the SU(3)),whereΓis an arbitrary open path(the same for all threeΦ’s)connecting points x0and y0,we represent the Wilson loop in(4)asW=SpW1SpW2SpW3−Sp(W1W2)SpW3−−Sp(W3W1)SpW2−Sp(W2W3)SpW1+(6)+Sp(W1W2W3)+Sp(W3W2W1)where(W i)αβis the ordered exponent along the contour formed by the paths of i-th quark andΓ.1The averaging over background was done using the cluster expansion method[3], generalized for the case of more than one Wilson loop as well as for a loop with selfintersection in[7].The main result of this method is that under assumption of existence of ﬁnite gluonic correlation length T g the generalized area law asymptotics may be obtained. For the Wilson loop(6)we write<W>B= Dz0exp(−σS1−σS2−σS3),(7) whereσis the string tension and S i is the minimal area inside the contour C i,and we integrate in(7)over the junction trajectories{z0}in accordance with our intention to treat a junction as a degree of freedom.The area law(7)is held for the contours with average size much larger than T g,and is violated only when the contours are nearly embedded into the same plane.In what follows we neglect such special conﬁgurations.We would like to note here,that the standard approach to the junction motion cor-responds to taking the classical trajectory z0(τ)in the integral(7)or,equivalently,as-suming 3i=1S i=min.The latter condition can be reduced in the potential model to the assumption that the sum of distances between quarks and junction is minimal.In the ”string-type”language the representation(7)means that we are interested in the special kinds of string excitations,which are absent for simple q¯q string conﬁgurations,and reveal themselves in multiquark systems.Using the parametrizationz iµ=(τ, r i),z0µ=(τ, r0)and introducing new dynamical variablesµi(τ)=T2µi +µi˙r2i2+σ 10dβi∂τ,w′iµ=∂w′iµ2µi +m i˙r2i2+σρi 10dβil i =1σ)to allow the adiabatic treatment of the problem.Following again the proceduce of[4]we introduce the auxiliaryﬁeldsνi,ηi:G= 3 i=1Dνi3 i=1Dηi3 i=1Dµi D r1D r2D r3D r0exp(−A[{ν},{η}]),(11)A[{ν},{η}]= T0dτ3 i=1 m2i2+µi2νi++14q22m s +r22m s+12 10dβν,(13)m s= 10dβνβ2,m sω2=σ2 10dβ2)2, r≡ r0, n= r2and r correspondingly.The adiabatic approximation means that one shouldﬁnd the eigenenergies E n of the ”fast”subsystem(13)as functions ofρ,and after that substitute E n(ρ)as adiabatic potentials into the Hamiltonian(12)of”slow”subsystem.To perform this program we ﬁrst found the classical equations of motion for the Hamiltonian(13)with the result(we restrict ourselves with the spherically symmetric case of L=0):E(a)=12 10dβν,(14)( Q n)=mωρ ρ2+r2,(15) where a is the constant of integration.It may be shown from equations(14),(15)that”freezing”of the junction degree of freedom actually means substitution the lowest classical energy E(0)into the Hamiltonian (12).In this case integration overνis trivial,and one arrives to the potential model Hamiltonian[1]2H=3m+p2+33m+√2m sω2ρ2(a2n+1)+32)πa2−x2√√√3σρ+(2n+3ρ.(20)We canﬁnd,however,the value ofρthat corresponds to the minimum of the potentialwell for quarks:ρ20=π(2n+32m sω2J(a(0)),(21)where for any n a(0)≈2.2is the root of the equation2aJ(a)−(a2+1)∂J(a)2The coeﬃcient at the conﬁnement form in(16)diﬀers slightly from one obtained by taking lowest hyperspherical harmonic of the interaction withσ 3i=1ρi=min.It happens because we integrate over theﬁeldνafter hyperspherical decomposition rather than before.The order of these procedures does not matter only if one does not truncate the basis.Performing the integration over νfor ρ0deﬁned from the equation (21),we arrive toνext =3(2n +3J (a (0))(1−β2)−1/2,(23)ρ20=4(n +3σJ (a (0)),E n =4(2n +3J (a (0))Having in mind that our quarks are heavy(m ≫√√2mρ2+E 0(ρ),(24)where L 2=15/4deﬁnes the ”hypercentrifugal”barrier for the lowest hyperspherical harmonic [10].In accordance with equations (17),(18)adiabatic potentials diverge at small ρ,or at large a 2n ,but this divergence is only the logarithmic one,as it is easily seen from the asymptotical behaviour of J (a )(see equation (19)).So for ”realistic”values of quark masses hypercentrifugal barrier dominates the eﬀective potential (24)at small values of ρ.Nevertheless,the spectrum of the ground state family diﬀers substantially from the one given by the potential model (16),and it happens due to the account of junction zero oscillations.The conﬁning force is not the whole story,and should be supplied by the Couloumb pair–wise interaction at small distances.Moreover,at small ρthe area law (7)is strongly contaminated by the eﬀects of ﬁnite correlation length T g ,so that the string regime does not develop itself at full scale.The 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