英美概况复习此为大学英语专业考试内容，下文含翻译。
USAI. Geography1. Geographic Features1.1 The Eastern HighlandsFormed by the Appalachian Range.?1. An average elevation of 800 meters above the sea level.?2. The highest peak:? Mount Mitchell (1856 m)：the highest peak of the Appalachian Range ?3. East: the narrow Atlantic Coast plain1.2 The Central Plains1. Vast plains between the Appalachian Mountains and the Rocky Mountains?2. Drained by the Mississippi River and its tributaries?3. Usually divided into two regions:?1) the Great Plains in the west: vast treeless prairies in the west and agricultural areas in the east?2) the Central Lowland in the east: from the five Great Lakes to central Texas1.3 The Western MountainsHigh plateaus and mountainous country?1. The Rocky Mountains: over 3,000 meters above the sea level?The continental divide of the United States ?2. West of the Rockies:? the Columbia Plateau in the north ?the Colorado Plateau in the southGrand Canyon,the Great Basin in between?The Pacific Mountain System consists of three regions: The Cascade Range, the Sierra-Nevada, and the Pacific Coast Range.?The Sierras contain Mount Whitney (4421m), the highest peak in the US outside Alaska.?Death Valley in eastern California, 85 meters below sea level2. ClimateThe United States has a large size and a wide range of geographic features. Every type of climate is represented in the country: The climate is temperate in most areas, tropical in Hawaii and southern Florida, polar in Alaska, semi-arid in the Great Plains west of the 100th meridian, desert in the Southwest, Mediterranean in Coastal California, arid in the Great Basin?Extreme weather is common: the states bordering the Gulf of Mexico are prone to hurricanes, and most of the world's tornadoes occur within the continental United States, primarily in the Midwest.3. RiversThe Mississippi River (Great River, Big River in Indian language) is 3,770 km long: the second longest river in the United States. It originates from Minnesota and empties into the Gulf of Mexico.?The Missouri River is 4,090 km long. It is the longest river (longest branch of the Mississippi). It is a Mississippi tributary, flowing from the confluence of the Jefferson, Madison, and Gallatin and emptying into the Mississippi River.The length of the Mississippi-Missouri-Jefferson combination is approximately 6,262 km?The Arkansas River (2,364 km) is the second longest tributary of the Mississippi River. The Ohio River is the largest Mississippi tributary measured by water volume.?The Yukon River is a major watercourse of northwestern North America. Rising in British Columbia, Canada, it runs 3,700 km long, emptying into the Bering Sea.5 great lakesII． American History1. Where did the first Americans come from and why did they migrate to America?Book P 4-52. American Civil warThe American Civil War (1861–1865), also known as the War Between the States, was a civil war in the United States of America. Eleven Southern slave states declared their secession from the U.S. and formed the Confederate States of America (the Confederacy). Led by Jefferson Davis, they fought against the U.S. federal government (the “Union”), which was supported by all the free states and the five border slave states.2.1 The CausesThe coexistence of a slave-owning South with an increasingly anti-slavery North made conflict likely. Lincoln did not propose federal laws against slavery where it already existed, but he had, in his 1858 House Divided Speech, expressed a desire to “arrest the further spread of it, and place it where the public mind shall rest in the belief that it is in the course of ultimate extinction”. Much of the political battle in the 1850s focused on the expansion of slavery into the newly created territories. All of the organized territories were likely to become free-soil states, which increased the Southern movement toward secession. Both North and South assumed that if slavery could not expand it would wither and die.The coexistence of a slave-owning South with an increasingly anti-slaveryNorth made conflict likely. Lincoln did not propose federal laws against slavery where it already existed, but he had, in his 1858 House Divided Speech, expressed a desire to “arrest the further spread of it, and place it where the public mind shall rest in the belief that it is in the course of ultimate extinction”. Much of the political battle in the 1850s focused on the expansion of slavery into the newly created territories. All of the organized territories were likely to become free-soil states, which increased the Southern movement toward secession. Both North and South assumed that if slavery could not expand it would wither and die. Southern fears of losing control of the federal government to antislavery forces, and Northern fears that the slave power already controlled the government, brought the crisis to a head in the late 1850s. Sectional disagreements over the morality of slavery, the scope of democracy and the economic merits of free labor vs. slave plantations caused the Whig and “Know-Nothing” parties to collapse, and new ones to arise (the Free Soil Party in 1848, the Republicans in 1854, the Constitutional Union in 1860). In 1860, the last remaining national political party, the Democratic Party, split along sectional lines.2.2 Factors Affecting the Process and ResultsWhat greatly affected the process as well as the result of the war were the differences between the South and the North in their strategies, geographical features, technology, and manpower and finance.2.2.1 StrategiesAs men poured into the armies, Northern and Southern leaders discussed strategies that would achieve victory.Northern armies would have to invade the Confederacy, destroy its capacity to wage war, and crush the will of the Southern people to resist. The Confederacy could win by prolonging the war to a point where the Northern people would consider the effort too costly in lives and money to persist.The South had a compelling example in the American Revolution of a seemingly weaker power defeating a much stronger one. If the North chose not to mount a military effort to coerce the seceded states back into the Union, the Confederacy would win independence by default.Lincoln and other Northern leaders, however, had no intention of letting the Southern states go without a fight. The most prominent American military figure in the spring of 1861 was Winfield Scott, the general-in-chief of the United States Army. With a brilliant mind, Scott conceived a long-range strategy to bring Northern victory. Scott’s plan sought to apply pressure on the Confederacy from all sides. A combined force of naval and army units would sweep down the Mississippi River, d ividing the Confederacy’s eastern and western states. At the same time, the Union navy would institute a blockade to deny the Confederacy access to European manufactured goods. Should the South continue to resist evenafter the loss of the Mississippi and the closing of its ports, Scott envisioned a major invasion into the heart of the Confederacy.2.2.2 GeographyGeography played a major role in how effectively the two sides were able to carry out their strategies.The sheer size of the Confederacy posed a daunting obstacle to Northern military forces. Totaling more than 1,940,000 km2 and without a well-developed network of roads, the Southern landscape challenged the North’s ability to supply armies that maneuvered at increasing distances from Union bases.It was also almost impossible to make the North’s blockade of Southern ports completely effective because the South’s coastline stretched 5600 km and contained nearly 200 harbors and mouths of navigable rivers.The Appalachian Mountains also hindered rapid movement of Northern forces between the eastern and western areas of the Confederacy while the Shenandoah Valley of Virginia offered a protected route through which Confederate armies could invade the North.The placement of Southern rivers, however, favored the North. The Mississippi, Tennessee, and Cumberland rivers provided excellent north-south avenues of advance for Union armies west of the Appalachians.2.2.3 TechnologyTechnological advances helped both sides deal with the great distances over which the armies fought. The Civil War was the first large conflict that featured railroads and the telegraph. Railroads rapidly moved hundreds of thousands of soldiers and vast quantities of supplies; the North contained almost twice as many miles of railroad lines as the South. Telegraphic communication permitted both governments to coordinate military movements on sprawling geographical fronts.The combatants also took advantage of numerous other recent advances in military technology. The most important was the rifle musket carried by most of the infantrymen on both sides. The rifle musket, with an effective range of 225 to 275 meters, allowed defenders to break up attacks long before they reached the defenders’ positions.Other new technologies included ironclad warships, which were used by both sides; the deployment of manned balloons for aerial reconnaissance on battlefields, used mainly by the North. The technology for all of these weapons had been present before the Civil War, but never before had armies applied the technology so widely.2.2.4 Manpower and FinanceAt the beginning of the war, state militias provided most of the troops for both Union and Confederate armies. Soon large numbers of civilianswere volunteering for military service. Throughout the war, the bulk of the forces consisted of volunteers.When the number of volunteers lagged behind the growing battle casualties, both the Northern and Southern governments resorted to drafting men into the armies. The Confederacy passed the first draft act in April 1862. The Union followed almost a year later.Although the draft itself did not produce a sufficient number of soldiers, the threat of being drafted led many to volunteer and collect a bounty, which was paid to volunteers. Some soldiers were unscrupulous enough to enlist, desert, and reenlist to collect the bounty more than once.The Civil War, like all wars, called for great sums of money to pay troops and supply them with equipment. At the outset of the war the Confederacy depended on loans, but this source of finance soon disappeared as Southerners began to be affected financially by the cost of the war and unable to buy bonds. Instead it relied on paper money, freely printed. The Confederacy suffered greatly from severe inflation and debt throughout the war. The Confederate rate of inflation was about 9200%.The Union financed its armies by loans and taxes to a much greater degree than the Confederacy, even resorting to an income tax. The people of the North were more prosperous than those of the South. A national banking system was established by Congress to stimulate sales of U.S. bonds. Northerners had savings with which they could buy the bonds and had earnings from which taxes could be taken.2.3 The Process2.6.1 Eastern Theater (1861-1863)2.6.3 Western Theater (1861-1863)2.6.4 Trans-Mississippi Theater (1861-1865)3. America in World War IWorld War I, military conflict, from August 1914 to November 1918, that involved many of the countries of Europe as well as the United States and other nations throughout the world.World War I was one of the most violent and destructive wars in European history.Of the 65 million men who were mobilized, more than 10 million were killed and more than 20 million wounded.The term World War I did not come into general use until a second worldwide conflict broke out in 1939. Before that year, the war was known as the Great War or the World War.1.1 Coalitions InvolvedThe war began as a clash between two coalitions of European countries.The first coalition, known as the Allied Powers, included the United Kingdom, France, Belgium, Serbia, Montenegro, and the Russian Empire.The Central Powers, which opposed them, consisted of the empires of Germany and Austria-Hungary.1.2 The Immediate CauseThe immediate cause of the war was the assassination of Archduke Francis Ferdinand, the heir to the throne of Austria-Hungary, by a Serbian nationalist.The fundamental causes of the conflict, however, were rooted deeply in the European history of the previous century, particularly in the political and economic policies that prevailed in Europe after 1871, the year that Germany emerged as a major European power.2. The Great DepressionOn October 24, 1929, the American stock market crashed. Billions of dollars of paper profits were wiped out within a few hours. This led to a long economic depression.However, the post-war industrial boom and the prosperity were soon to vanish. The Great Depression in the United States, worst and longest economic collapse in the history of the modern industrial world, began from the end of 1929 until the early 1940s.2.1 The CausesThe depression was caused by a number of serious weaknesses in the economy.It is a common misconception that the stock market crash of October 1929 was the cause of the Great Depression. The two events were closely related, but both were the results of deep problems in the modern economy that were building up through the “prosperity decade” of the 1920s.As is typical of post-war periods, Americans in the Roaring Twenties turned inward, away from international issues and social concerns and toward greater individualism.The self-centered attitudes of the 1920s seemed to fit nicely with the needs of the economy. Modern industry had the capacity to produce vast quantities of consumer goods, but this created a fundamental problem: Prosperity could continue only if demand was made to grow as rapidly as supply. Accordingly, people had to be persuaded to abandon such traditional values as saving, postponing pleasures and purchases, and buying only what they needed. Advertising methods were used to persuade people to buy such relatively new products as automobiles and such completely new ones as radios and household appliances. The resulting mass consumption kept the economy going through most of the 1920s.But there was an underlying economic problem: Income was distributed very unevenly, and the portion going to the wealthiest Americans grew larger as the decade proceeded. This was due largely to two factors: While businesses showed remarkable gains in productivity during the 1920s, workers got a relatively small share of the wealth this produced. Between 1923 and 1929, manufacturing output per person-hour increased by 32 percent, but workers’ wages grew by only 8 percent. Corporate profits shot up by 65 percent in the same period.As a result of these trends, in 1929 the top 0.1 percent of American families had a total income equal to that of the bottom 42 percent. This meant that many people who were willing to purchase new products did not have enough money to do so. To get around this difficulty, the 1920s produced another innovation—“credit,” an attractive name for consumer debt. People were allowed to “buy now, pay later.”International problems also weakened the economy. After World War I the United States became the world’s chief creditor as European countries struggled to pay war debts and reparations. Many American bankers were not ready for this new role. They lent heavily and unwisely to borrowers in Europe, especially Germany, who would have difficulty repaying the loans, particularly if there was a serious economic downturn. These huge debts made the international banking structure extremely unstable by the late 1920s.In addition, the United States maintained high tariffs on goods imported from other countries, at the same time that it was making foreign loans and trying to export products. This combination could not be sustained: If other nations could not sell their goods in the United States, they could not make enough money to buy American products or repay American loans.The rising incomes of the wealthiest Americans fueled rapid growth in the stock market, especially between 1927 and 1929. Soon the prices of stocks were rising far beyond the worth of the shares of the companies they represented. People were willing to pay inflated prices because they believed the stock prices would continue to rise and they could soon sell their stocks at a profit.In 1928 the Dow Jones industrial average, an index that tracks the stock prices of key industrial companies, doubled in value in less than two years. But the stock boom could not last. The great bull market of the late 1920s was a classic example of a specul ative “bubble” scheme. In the fall of 1929 confidence that prices would keep rising faltered, then failed.Starting in late October the market plummeted as investors began selling stocks. On October 29, known as Black Tuesday, the worst day of the panic, stocks lost $10 billion to $15 billion in value. By mid-November almost all of the gains of the previous two years had been wiped out, withlosses estimated at $30 billion.The stock market crash announced the beginning of the Great Depression.2.3 R oosevelt’s New DealThe initial government response to the Great Depression was ineffective, as President Hoover insisted that the economy was sound and that prosperity would soon return.But business owners saw no reason to increase production while unsold goods clogged their shelves. By 1932 investment had dropped to less than 5 percent of its 1929 level. By the election year of 1932, the depression had made Hoover so unpopular that the election of the Democratic presidential candidate Franklin Delano Roosevelt was all but assured. Shortly after his inauguration in 1933, Roosevelt quickly lifted the nation’s spirits with the rapid and unprecedented actions of the New Deal.The New Deal produced a wide variety of programs to reduce unemployment, assist businesses and agriculture, regulate banking and the stock market, and provide security for the needy, elderly, and disabled. The basic idea of early New Deal programs was to lower the supply of goods to the current, depressed level of consumption. The government sought to raise farm prices by paying farmers not to grow surplus crops and to create codes for many industries that regulated competition while guaranteeing minimum wages and maximum hours for workers. The New Deal also tried to increase demand, pumping large amounts of money into the economy through public works programs and relief measures.Public works projects not only provided jobs but built schools, dams, and roads. The New Deal helped people to survive the depression. Unemployment was reduced, but remained high through the 1930s. Farm income rose from a low of $1.9 billion in 1932 to $4.2 billion in 1940. The demands of the depression led the United States to institute social-security programs and accept labor unions, measures that had been taken decades earlier in many European nations.3.2.1 US and Japanese ConflictIn the final result, however, the United States had little choice in the matter. When France had fallen to Germany, Japan had begun to move into French Indo-China, which had been France's source of rubber and was thought to be rich in oil. The United States government had no desire to see Japan in possession of its own stocks of these essential resources and so threatened to place an embargo on these goods. The Japanese responded in an unexpected way. On Sunday, 7 December 1941, Japanese naval aircraft attacked the U.S. Pacific fleet at anchor at Pearl Harbor in the Hawaiian islands. The Pearl Harbor Attack brought the United States into the war on December 8. Germany and Italy declared war on the United Stateson DecemberThe CongressThe United StatesCongress is the bicameral legislature of the federal government of the United States of America, consisting of two houses, the Senate and the House of Representatives. Both senators and representatives are chosen through direct election.As provided by the United States Constitution, each of the 435 members of the House of Representatives represents a district and serves a two-year term. House seats are apportioned among the states by population. The 100 Senators serve staggered six-year terms. Each state has two senators, regardless of population. Every two years, approximately one-third of the Senate is elected.checks and balances:The government is divided into three branches, the legislative, the executive and the judicial, each has part of the powers but not all the power. And each branch of government can check, or block, the actions of the other branches. The three branches are thus in balance. This called “checks and balances”.What is American General Education?见书English2.1 The Iberians1) They are the earliest settlers on the British Isles.2.2 The Celts1) From 700 B.C. Celts came in several successive waves from the Upper Rhineland and began to inhabit British Isles.2) The fair-haired Celts imposed themselves as an aristocracy on the conquered tribes of Iberians throughout Britain and Ireland.3) These people found refuge in the mountains to the north and west.4) At least two big waves of Celtic invasion can be distinguished: first the Gaels or Goidels, still found in Ireland and Scotland, came over as early as 600 B.C.; secondly the Cymric and Brythons, still found in Wales, come over before 300 B.C.3. Roman Britain3.1 Roman InvasionRoman Britain refers to those parts of the island of Great Britain controlled by the Roman Empire between AD 43 and 410.The Romans referred to their province as Britannia.Prior to the Roman invasion, Iron Age Britain already had cultural and economic links with Continental Europe, but the invaders introduced new developments in agriculture, urbanization, industry and architecture, leaving a legacy that is still apparent today.It is believed that the Celts were related with the ancient people in what is now France. They gave some help in the struggle to resist the Roman invasion of France. As a result, the Roman army, commanded by Julius Caesar, invaded England in 55 BC. He landed in Kent with several thousand Roman troops, but meeting resistance and bad weather, the Roman withdrew soon after. In the following year, Julius Caesar and the Romans went across the English Channel and invaded Britain for the second time. Julius Caesar and his soldiers did not stay long in England before they withdrew again. The invasion marked the beginning of English recorded history because Julius Caesar kept a diary and wrote down what he saw in England. The successful invasion of England by the Romans did not take place until nearly a century later, in 43 AD, headed by the Emperor Claudius I. The Romans did not meet with much resistance on the part of the natives and soon got possession of what is now England by driving many of the native Celts into mountainous Scotland and Wales. The Romans failed to conquer Scotland, they built two great walls, the Hadrian’s Wall and the Antonine Wall, along the northern border of England to prevent the Picts in Scotland from invading England.3.2 Influences of Roman InvasionThe 3d and 4th centuries witnessed the decline of the Roman Empire. In 410 Rome abandoned Britain.1. Roman urban civilization, baths and amphitheaters, as well Hadrian’s Wall. People who spoke Latin and wore togas. Numerous villas——vast estates worked by slaves and featuring sumptuous noble dwellings—were also established. Beyond these, the countryside remained Celtic.2. A network of roads, still in use for 1400 years;3. A number of towns. They introduced a system of organized government and built a network of towns, mostly walled. These town used names ending with “ster”, “cester”, or “shire” -- Leicester, Worcester and Yorkshire—deriving from castra, the Latin word for camp; the Roman capital was London.4. Christianity; the Romans brought the new religion, Christianity, to Britain. This came at first by indirect means, probably brought by traders and soldiers, before the first Christian Emperor, Constantine, we proclaimed in 306 AD.5. Water and sewage systems.1.1 Anglo-SaxonSoon after the Romans left, a band of new invaders landed in the southern part of England, in what is now the country of Kent. They were known in history as the Jutes. Other Germanic tribes came trooping after them. This continued for many years. The Saxons came from northern Germany and established their kingdoms in Essex (East Saxow), Succes (South Saxon) and Wessex (West Saxon). In the second half of the 6th century, the Angles, also from northern Germans, came and settled in the east part of England. After the newcomers had taken possession of all the land now known as England, the movement, know in history as the Anglo-Saxon Conquest, was complete. But we must bear in mind that theses Germanic tribes never obtained possession of what we now call Scotland, Wales and Ireland. The inhabitants of these countries were still Celts.The England was divided into seven principal kingdoms, known as Heptarchy in English history: Northumbria, Mercia, Kent, East Anglia, Essex, Sussex and Wessex were the main polities of south Britain.The influence of Anglo-Saxon?The Anglo-Saxons laid the foundations of the English state. They divided the country into shires, with shire courts and shire reeves, or sheriffs, responsible for administering law.?They devised the narrow-strip, three-field farming system which continued to the 18th century. In this system, the arable land around a village was divided into three hedgeless (open) big fields. These fields were divided into narrow strips which were shared out among the villagers. Good land was thus fairly distributed. One great field was left “fallow” each year so that its soil could recover its richness after two years’ cultivation.?They set up the basis of the English agrarian civilization and subsistence farming. There were wastelands, known as commons, which were used by villagers to graze livestock and get firewood. This system was the basis of the English agrarian civilization and subsistence farming. It helped to shape the English community life and the Anglo-Saxon concept of equality.?They created the Witan（council or meeting of the wisemen） to advise the king, the basis of the Privy Council which still exists today.2. Viking Invasion (800–1066)In the 8th century, the Vikings from theScandinavian countries of northern Europe, Norway and Denmark, began to attack the English coast. In the process of resisting the Vikings, the 7 Anglo-Saxon kingdoms in England gradually became united under Alfred the Great.Alfred was a king of Wessex. He was not only an able warrior but also adedicated scholar and a wise ruler. He defeated the Danes and reached a friendly agreement with them in 879. The Danes gained control of the north and east, while he ruled the rest. He also converted some leading Danes into Christians.He founded a strong fleet and is known as “ the father of the British navy”. He reorganized the Saxon army, making it more efficient. He translated a Latin book into English. He also established schools and formulated a legal system.After the death of Alfred, his successors were not as capable as he had been. Taking advantage of the situation, more Dane came and set about taking possession of the entire country. The Anglo-Saxon king didn’t care for fighting, but he dreamed of buying off the Danes. As a result, more invaders came. In 1016, the Witan chose Canute, the Danish leader, as king of England. Canute, who made England part of a Scandinavian empire which included Norway as well as Denmark.3. Norman Conquest3.1 Norman Conquest: CauseAfter the death of Canute’s son, the crown was passed to Edward the Confessor, the last Anglo-Saxon king.When Edward was on his death-bed, several men laid claim to the English throne, the king of Norway, the Duke of Normandy (Edward’s cousi n), and Harold Godwinson( a brother of Edward’s wife).William, the Duke of Normandy, claimed the Edward had promised the crown to him before his death. He became very angry when he heard that Harold had taken the crown. Harold knew that William would come to measure swords with him. he was prepared to fight, placing an army on the southern coast of England to watch for William’s coming. Several months passed by and William failed to appear. He was abiding his time. When the harvest time in England came, ma ny of Harold’s soliders went back home to gather in the crops/. The coast was thus left undefended.William seized the chance and landed his army in Southeastern England in Sep. 1066. Harold, who had been fighting in the north, hurried back with the exhausted troops. They fought at the Battle of Hastings on 14 October. It was a close battle at first, but in the final hours William’s superiority in cavalry and archers proved decisive. Harold was killed, along with his brothers Earl Gyrth and Earl Leofwine, and the English army fled.William became known as William the Conqueror, the first Anglo-Norman king of England.3.2 Control of EnglandAfter Willam became the king, he took a few measures to control England Soldiers rewarded: The Normans received from William lands and titles in return for their service in the invasion.All land was the king’s: William claimed ultimate possession of。
英美概况知识点总结归纳英美概况是指英国和美国的文化、历史、政治、经济、教育等各方面的概况。
这两个国家在世界上具有重要的地位，对世界文化和政治产生了深远的影响。
下面将对英美概况的各个方面进行总结归纳。
一、文化概况1. 英国文化英国是一个拥有悠久历史的国家，其文化底蕴深厚。
英国文学自古至今在世界范围内具有重要地位，莎士比亚、狄更斯、奥斯丁等众多文学家的作品至今仍然备受人们喜爱。
英国音乐、戏剧、电影等领域也有着丰富的传统。
2. 美国文化美国是一个移民国家，因此其文化融合了来自世界各地的元素，呈现出多元化和包容性。
美国文学、音乐、电影等在世界上具有很大影响力，如杰克·伦敦、海明威、福克纳等作家的作品、爵士乐、摇滚乐、好莱坞电影等都深受人们喜爱。
3. 英美文化交流英美两国之间的文化交流十分频繁，互相影响。
英国音乐、戏剧、文学等在美国具有很大影响力，而美国的流行音乐、电影、文化现象也在英国广受欢迎。
二、历史概况1. 英国历史英国历史可以追溯到古代，罗马、盎格鲁-撒克逊、诺曼底人等不同民族和文化在英国留下了深远的影响。
英国从16世纪开始成为世界上的帝国大国，殖民了大量领土。
20世纪初，英国逐渐衰落，但仍然在政治、文化方面占有重要地位。
2. 美国历史美国历史相对年轻，但是却是一个充满传奇色彩的国家。
美国独立战争后成为独立国家，并在19世纪成为世界上最强大的国家之一。
20世纪，美国在两次世界大战后成为世界超级大国，对世界政治、经济产生了深远影响。
3. 英美历史关系英国曾是美国的殖民地，双方有着深厚的历史渊源。
美国革命后，两国保持了密切的关系，经济、文化、政治等方面有着广泛的交流合作。
三、政治概况1. 英国政治英国是一个君主立宪制国家，国家元首是君主，首相是政府首脑。
英国的政治体系成熟稳定，经过数百年的发展，形成了一套完善的议会制度和法律体系。
2. 美国政治美国是一个总统制国家，总统是国家元首和政府首脑。
