机经词汇：
pertinent=relevant
accrodingly=correspondingly
enormousl=huge
cluter=group
inevitable=certain
simultaneously=at the same time
subdue=defeat
justify=?
coincide with=?
presumable=?
第一篇：
版本1:
文章先讲太阳系里的东西都有相同的起源。先是说所有的东西是在一起的，然后说地球由于地表的水、火山活动和一个什么过程使得地球连最古老的石头都没有了。所以只能测定月球的陨石的成分了，结论是月球的表面和陨石的时间都是46亿年。因为月球表面没有地球的这些活动，所以可以测定。
后面又说宇宙的星系都在不断地拉开距离，通过星系的红移可以确定距离还有速度，发现宇宙一直在膨胀。发现宇宙在137亿年前是一个点。然后就有了宇宙大爆炸。
版本2： 讲地球和宇宙年龄的测量。先说太阳系大部分物质是同一时间形成的，然后说地球年龄难是因为谁腐蚀。接着引入一种物质，可以通过同位素测年龄。结果是和月球上的最古老的石头近似。然后说宇宙在膨胀，大爆炸。通过红移测年龄。
版本3： 天文类， 某种地球上的物质和月球上最古老的物质证明他。都始于自4.6million年前，于是证明太阳系的年龄是4.6 Million years. 另外还有种通过判断各星球一种wavelength的大小推断出他们在多少年前都是从个spot发展出来，于是判断了big bang的时间。
词汇：
origin 起源
meteorite 陨石
galaxy 星系
expansion 膨胀
red shift 红移
wavelength 波长
解析：
天文主题文章的词汇专业性较强，需要提前对相关专题的TPO文章的生词熟悉，尽量减少生词恐惧带来的内耗。另外，出现天文理论的文章，结构通常都会比较清晰，但要着重识别对理论内容的态度倾向。
相关背景：
a.Big Bang
The Big Bang theory is the prevailing cosmological model for the early development of the universe. According to the theory, the Big Bang occurred approximately 13.82 billion years ago, which is thus considered the age of the universe. At this time, the universe was in an extremely hot and dense state and was expanding rapidly. After the initial expansion, the universe cooled sufficiently to allow the formation of subatomic particles, including protons, neutrons, and electrons. Though simple atomic nuclei formed within the first three minutes after the Big Bang, thousands of years passed before the first electrically neutral atoms formed. The majority of atoms that were produced by the Big Bang are hydrogen, along with helium and traces of lithium. Giant clouds of these primordial elements later coalesced through gravity to form stars and galaxies, and the heavier elements were synthesized either within stars or during supernovae.
b.Accelerating universe
The accelerating universe is the observation that the universe appears to be expanding at an increasing rate. In formal terms, this means that the cosmic scale factor has a positive second derivative,[1] so that the velocity at which a distant galaxy is receding from us should be continuously increasing with time.[2] In 1998, observations of type Ia supernovae also suggested that the expansion of the universe has been accelerating[3][4] since around redshift of z~0.5.[5] The 2006 Shaw Prize in Astronomy and the 2011 Nobel Prize in Physics were both awarded to Saul Perlmutter, Brian P. Schmidt, and Adam G. Riess, who in 1998 as leaders of the Supernova Cosmology Project (Perlmutter) and the High-Z Supernova Search Team (Schmidt and Riess) discovered the accelerating expansion of the Universe through observations of distant ("High-Z") supernovae.[6][7]
observations.[edit]
The simplest evidence for accelerating expansion comes from the brightness/redshift relation for distant Type-Ia supernovae; these are very bright exploding white dwarfs, whose intrinsic luminosity can be determined from the shape of the light-curve. Repeated imaging of selected areas of sky is used to discover the supernovae, and then followup observations give their peak brightness and redshift. The peak brightness is then converted into a quantity known as luminosity distance (see distance measures in cosmology for details).
For supernovae at redshift less than around 0.1, or light travel time less than 10 percent of the age of the universe, this gives a nearly linear redshift/distance relation due to Hubble's law. At larger distances, since the expansion rate of the universe has generally changed over time, the distance/redshift relation deviates from linearity, and this deviation depends on how the expansion rate has changed over time. The full calculation requires integration of the Friedmann equation, but the sign of the deviation can be given as follows: the redshift directly gives the cosmic scale factor at the time the supernova exploded, for example a supernova with a measured redshift implies the Universe was of its present size when the supernova exploded. In an accelerating universe, the universe was expanding more slowly in the past than today, which means it took a longer time to expand from 2/3 to 1.0 times its present size compared to a non-accelerating universe. This results in a larger light-travel time, larger distance and fainter supernovae, which corresponds to the actual observations: when compared to nearby supernovae, supernovae at substantial redshifts 0.2 - 1.0 are observed to be fainter (more distant) than is allowed in any homogeneous non-accelerating model.
Corroboration[edit]
After the initial discovery in 1998, these observations were corroborated by several independent sources: the cosmic microwave background radiation and large scale structure,[8] apparent size of baryon acoustic oscillations,[9] age of the universe,[10] as well as improved measurements of supernovae,[11][12] X-ray properties of galaxy clusters and Observational H(z) Data.[13]
Explanatory models[edit]
Models attempting to explain accelerating expansion include some form of dark energy, dark fluid or phantom energy. The most important property of dark energy is that it has negative pressure which is distributed relatively homogeneously in space. The simplest explanation for dark energy is that it is a cosmological constant or vacuum energy; this leads to the Lambda-CDM model, which has generally been known as the Standard Model of Cosmology from 2003 through the present, since it is the simplest model in good agreement with a variety of recent observations. Alternatively, some authors (e.g. Benoit-Lévy & Chardin[14], Hajdukovic[15], Villata[16]) have argued that the universe expansion acceleration could be due to a repulsive gravitational interaction of antimatter.
Theories for the consequences to the universe[edit]
As the Universe expands, the density of radiation and ordinary and dark matter declines more quickly than the density of dark energy (see equation of state) and, eventually, dark energy dominates. Specifically, when the scale of the universe doubles, the density of matter is reduced by a factor of 8, but the density of dark energy is nearly unchanged (it is exactly constant if the dark energy is a cosmological constant).
Current observations indicate that the dark energy density is already greater than the mass-energy density of radiation and matter (including dark matter). In models where dark energy is a cosmological constant, the universe will expand exponentially with time from now on, coming closer and closer to a de Sitter spacetime. In this scenario the time it takes for the linear size scale of the universe to expand to double its size is approximately 11.4 billion years. Eventually all galaxies beyond our own local supercluster will redshift so far that it will become hard to detect them, and the distant universe will turn dark.
In other models, the density of dark energy changes with time. In quintessence models it decreases, but more slowly than the energy density in ordinary matter and radiation. In phantom energy models it increases with time, leading to a big rip.
第二篇：
版本一：某些动物长大以后离开出生地生存，有些不会。主要讲不可以的。举了两个例子。第一个是松鼠，雄鼠长大后飞走，雌鼠不会。第二个例子是狮子，雄狮子长大了以后会离开，原因是打不过原来的首领，被赶跑。雌性狮子则会留在群落帮忙找吃的。
版本二：讲动物离开出生点行为，原因一：某鼠离开出生点，雄150米，雌50米，因为能防止近亲繁殖导致基因病，同时雌性在一起能养小鼠方便。原因二：狮子，群内争斗呀，劳什子排挤呀什么的。
版本三： 动物的disperse, 刚开始说为什么动物要离开熟悉的food rich的地方而去其他地方。其中讲了一种动物男女的分布是不一样的，女的离原来的家50米，男的150米， 不同的原因是防止近亲结婚导致孩子多病不易存活，另外女的离家近更有益处，家里可以给她提供保护，然后男的要更远的地方对抗敌人，有可能被竞争者replace而离开，然后有个lion的例子
词汇：
squirrel n松鼠
disperse v分散
Inbreeding n近亲交配
genopathy n遗传病
解析：本文围绕动物为何离开出生地这个主题展开论证。做题时需注意记录笔记，对于结构化阅读及最后一题的解答有很大好处。动物行为主题是
相关背景：
Animal Inbreeding
Inbreeding is the production of offspring from the mating or breeding of individuals or organisms which are closely related genetically, in contrast to outcrossing, which refers to mating unrelated individuals.[1] By analogy, the term is used in human reproduction, but more commonly refers to the genetic disorders and other consequences that may arise from incestuous sexual relationships and consanguinity.
Inbreeding results in homozygosity, which can increase the chances of offspring being affected by recessive or deleterious traits.[2] This generally leads to a decreasedbiological fitness of a population,[3][4] (called inbreeding depression) which is its ability to survive and reproduce. An individual who inherits such deleterious traits is referred to as inbred. The avoidance of such deleterious recessive alleles caused by inbreeding is the main selective reason for outcrossing.[5][6]
Inbreeding is a technique used in selective breeding. In livestock breeding, breeders may use inbreeding when, for example, trying to establish a new and desirable traitin the stock, but will need to watch for undesirable characteristics in offspring, which can then be eliminated through further selective breeding or culling. Inbreeding is used to reveal deleterious recessive alleles, which can then be eliminated through assortative breeding or through culling. In plant breeding, inbred lines are used as stocks for the creation of hybrid lines to make use of the effects of heterosis. Inbreeding in plants also occurs naturally in the form of self-pollination.
Offspring of biologically related persons are subject to the possible impact of inbreeding, such as congenital birth defects. The chances of such disorders is increased the closer the relationship of the biological parents. (See coefficient of inbreeding.) This is because such pairings increase the proportion of homozygous zygotes in the offspring, in particular deleterious recessive alleles, that produce such disorders.[7] (See inbreeding depression.) Because most recessive alleles are rare in populations, it is unlikely that two unrelated marriage partners will both be carriers of the alleles. However, because close relatives share a large fraction of their alleles, the probability that any such deleterious allele is inherited from the common ancestor through both parents is increased dramatically. Contrary to common belief, inbreeding does not in itself alter allele frequencies, but rather increases the relative proportion of homozygotes to heterozygotes. However, because the increased proportion of deleterious homozygotes exposes the allele to natural selection, in the long run its frequency decreases more rapidly in inbred population. In the short term, incestuous reproduction is expected to produce increases in spontaneous abortions of zygotes, perinatal deaths, and postnatal offspring with birth defects.[8]
There may also be other deleterious effects besides those caused by recessive diseases. Thus, similar immune systems may be more vulnerable to infectious diseases (seeMajor histocompatibility complex and sexual selection).[9]
第三篇：
版本一： 讲某个文明，说多个原因导致其发展。一是葡萄藤和橄榄树的引入，和传统农作物不冲突，无论土地还是收获期。这使人们可以从事其他如炼金属青铜什么的。然后这导致了不同group的争斗，争夺资源和specialist。总体和某个TPO阅读很像。
版本二：讲希腊文明，全文大意一句总结：traditional analysis focused on external influences,but the professor thinks from the perspective of MUTILIER EFFECT(考点)，which combined several interal impacts.
版本三：地中海地区某一时间一些国家的发展 A国发展之一种了Oliva什么的一种长在岛上不用在Farm上而且工人对这种作物的劳动时间也和其他作物不一样，所以能大力发展，还有一种是Bronze的发展
解析： 本文讲文明发展史。主要讨论的是某文明发展的原因，主旨明确，结构清晰，每段首句为topic sentence的可能性较高。大家在阅读文章之前可以先跳到最后一题(文章总结题)的位置看看那句对于文章总结的句子。对于大家从整体上把握文章的结构非常有帮助。从文章结构与内容上，都非常接近TPO8的文章The Rise of Teotihucan。
相关背景：
Sumer
Sumer (from Akkadian Šumeru; Sumerian ki-en-ĝir15, approximately "land of the civilized kings" or "native land"[note 1]) was an ancientcivilization and historical region in southern Mesopotamia, modern-day southern Iraq, during the Chalcolithic and Early Bronze Age. Although the earliest forms of writing in the region do not go back much further than c. 3500 BC, modern historians have suggested that Sumer was first permanently settled between c. 5500 and 4000 BC by a non-Semitic people who may or may not have spoken the Sumerian language (pointing to the names of cities, rivers, basic occupations, etc. as evidence).[1][2][3][4] These conjectured, prehistoric people are now called "proto-Euphrateans" or "Ubaidians",[5] and are theorized to have evolved from the Samarra culture of northern Mesopotamia (Assyria).[6][7][8][9] The Ubaidians were the first civilizing force in Sumer, draining the marshes for agriculture, developing trade, and establishing industries, including weaving, leatherwork, metalwork, masonry, and pottery.[5] However, some scholars such as Piotr Michalowski and Gerd Steiner, contest the idea of a Proto-Euphratean language or one substrate language. It has been suggested by them and others, that the Sumerian language was originally that of the hunter and fisher peoples, who lived in the marshland and the Eastern Arabia littoral region, and were part of theArabian bifacial culture.[10] Reliable historical records begin much later; there are none in Sumer of any kind that have been dated beforeEnmebaragesi (c. 26th century BC). Professor Juris Zarins believes the Sumerians were settled along the coast of Eastern Arabia, today's Persian Gulf region, before it flooded at the end of the Ice Age.[11] Sumerian literature speaks of their homeland being Dilmun.
Sumerologist Samuel Noah Kramer asserts "No people has contributed more to the culture of mankind than the Sumerians" and yet it is only comparatively recently that we have built up a knowledge of the existence of this ancient culture.[12] Sumerian civilization took form in theUruk period (4th millennium BC), continuing into the Jemdat Nasr and Early Dynastic periods. During the 3rd millennium BC, a close cultural symbiosis developed between the Sumerians (who spoke a language isolate) and the Semitic Akkadian speakers, which included widespreadbilingualism.[13] The influence of Sumerian on Akkadian (and vice versa) is evident in all areas, from lexical borrowing on a massive scale, tosyntactic, morphological, and phonological convergence.[13] This has prompted scholars to refer to Sumerian and Akkadian in the 3rd millennium BC as a sprachbund.[13] Sumer was conquered by the Semitic-speaking kings of the Akkadian Empire around 2270 BC (short chronology), but Sumerian continued as a sacred language. Native Sumerian rule re-emerged for about a century in the Third Dynasty of Ur (Sumerian Renaissance) of the 21st to 20th centuries BC, but the Akkadian language also remained in use. The Sumerian city of Eridu, on the coast of the Persian Gulf, was the world's first city, where three separate cultures fused - that of peasant Ubaidian farmers, living in mud-brick huts and practicing irrigation; that of mobile nomadic Semitic pastoralists living in black tents and following herds of sheep and goats; and that of fisher folk, living in reed huts in the marshlands, who may have been the ancestors of the Sumerians.[14]
The irrigated farming together with annual replenishment of soil fertility and the surplus of storable food in temple granaries created by this economy allowed the population of this region to rise to levels never before seen, unlike those found in earlier cultures of shifting cultivators. This much greater population density in turn created and required an extensive labour force and division of labour with many specialised arts and crafts. At the same time, historic overuse of the irrigated soils led to progressive salinisation, and a Malthusian crisis which led to depopulation of the Sumerian region over time, leading to its progressive eclipse by the Akkadians of middle Mesopotamia.
Sumer was also the site of early development of writing, progressing from a stage of proto-writing in the mid 4th millennium BC to writing proper in the 3rd millennium BC (see Jemdet Nasr period).