The story of the westward movement ofpopulationin the United States is, in the main, the story of theexpansionof Americanagriculture—of thedevelopmentof new areas for the raising oflivestockand thecultivationof wheat, corn, tobacco, and cotton. After 1815 improvedtransportationenabled more and more western farmers toescapeaself-sufficientway of life and enter a nationalmarketeconomy. During periods whencommodityprices were high, therateof westwardmigrationincreased spectacularly. "Old America seemed to be breaking up and moving westward," observed an English visitor in 1817,during the first great wave ofmigration. Emigration to the West reached apeakin the 1830's. Whereas in 1810 only a seventh of the American people lived west of the Appalachian Mountains, by 1840 more than a third lived there.

Why were these hundreds of thousands of settlers—most of them farmers, some of them artisans—drawn away from the cleared fields and established cities and villages of the East? Certain characteristics of American society help to explain thisremarkablemigration. The European ancestors of some Americans had for centuries lived rooted to the same village or piece of land until somereligious,political, oreconomiccrisis uprooted them and drove themacrossthe Atlantic. Many of those who experienced this sharpbreakthereafter lacked the ties that hadboundthem and their ancestors to a single place. Moreover, European society wasrelativelystratified; occupation and socialstatuswereinherited. In American society, however, the class structure was lessrigid; some people changed occupations easily and believed it was their duty toimprovetheir social andeconomicposition. As a result, many Americans were an inveterately restless, rootless, andambitiouspeople. Therefore, these social traits helped to produce thenomadicanddaringsettlers who kept pushing westward beyond the fringes ofsettlement. Inaddition, there were other immigrants who migrated west in search of new homes,materialsuccess, and better lives.

The West had plenty of attractions: thealluvialriver bottoms, the fecund soils of the rolling forest lands, the black loams of the prairies were tempting to New England farmers working theirrocky,sterileland and to southeastern farmers plagued with soil depletion anderosion. In 1820 under a new land law, a farm could be bought for $100. The continuedproliferationof banks made it easier for those without cash to negotiate loans in paper money. Western Farmers borrowed with the confident expectation that the expandingeconomywould keep farm prices high, thus making it easy to repay loans when they felldue.

Transportationwas becoming less of a problem for those who wished to move west and for those who had farm surpluses to send tomarket.Priorto 1815, western farmers who did not live on navigable waterways were connected to them only by dirt roads and mountain trails.Livestockcould be drivenacrossthe mountains, but thecostof transportingbulkygrains in thisfashionwas several times greater than their value in eastern markets.The first step toward an improvement of westerntransportationwas theconstructionof turnpikes.These roads made possible areductionintransportationcosts and thusstimulatedthecommercializationofagriculturealongtheir routes. Priorto 1815, western farmers who did not live on navigable waterways were connected to them only by dirt roads and mountain trails. Livestockcould be drivenacrossthe mountains, but thecostof transportingbulkygrains in thisfashionwas several times greater than their value in eastern markets. The first step toward an improvement of westerntransportationwas theconstructionof turnpikes. These roads made possible areductionintransportationcosts and thusstimulatedthecommercializationofagriculturealongtheir routes.

Two other developments presaged the end of theeraof turnpikes and started atransportationrevolutionthat resulted in increased regionalspecializationand the growth of a nationalmarketeconomy. First came thesteamboat; although flatboats and keelboats continued to be important until the 1850’s steamboatseventuallysuperseded all othercraftin the carrying of passengers andfreight. Steamboats were not only faster but also transported upriverfreightfor about one tenth of what it hadpreviouslycoston hand-propelled keelboats. Next came the ErieCanal, anenormousprojectin its day, spanning about 350 miles. After thecanalwent into operation, thecostper mile of transporting a ton offreightfromBuffaloto New York City declined from nearly 20 cents to less than 1 cent. Eventually, the western states diverted much of their produce from the rivers to the ErieCanal, a shorterrouteto eastern markets.

Questions:
question_stem: What can be inferred from paragraph 1 about western farmers prior to 1815?
choices: tag: A
text: They had limited their crop production to wheat, corn, tobacco, and cotton.

tag: B
text: They were able to sell their produce at high prices.

tag: C
text: They had not been successful in raising cattle.

tag: D
text: They did not operate in a national market economy.
answer_key: D
explanation: D 以1815做关键词定位至第二句，说1815年之后，交通的改善使得更多农民不再自给自足，进入全国范围内的市场经济，也就是说1815年之前是自给自足不参与市场经济的，所以答案是 D。其他选项都无关

question_stem: What is the purpose of the statement, “Whereas in 1810 only a seventh of the American people lived west of the Appalachian Mountains, by 1840 more than a third lived there”?
choices: tag: A
text: To illustrate that generally population shifts occur rapidly

tag: B
text: To correct a mistaken impression of American agriculture from 1810 to 1840

tag: C
text: To emphasize the range and speed with which the westward migration occurred

tag: D
text: O To demonstrated how attractive the Appalachian Mountains were to Americans
answer_key: C
explanation: C  修辞目的题，先读例子所在句子，说向西的移民潮在30年代达到顶峰，接着就给出具体数字来解释，所以是为了说明移民的数量和范围很广，之所以说范围，是因为例子提到阿巴拉契亚山脉以西，所以答案是 C。A 只说速度，不全面；B 没有 mistaken view；D 说阿巴拉契亚有吸引力纯属扯淡。

question_stem: The word "fringes" in the passage is closest in meaning to
choices: tag: A
text: borders

tag: B
text: groups

tag: C
text: types

tag: D
text: directions
answer_key: A
explanation: A, fringe: 边缘，次要，额外补贴。A 是边缘；B 是族群；C 是种类；D 是方向。所以正确答案是 A 的 border。

question_stem: According to paragraph 2, all of the following are reasons why Americans migrated westward EXCEPT
choices: tag: A
text: the desire to move from one place to the next

tag: B
text: the hope of improving their socioeconomic status

tag: C
text: the opportunity to change jobs

tag: D
text: the need to escape religious or political crises
answer_key: D
explanation: D EXCEPT 题，但这道题用正选更好。以 reason 做关键词定位至第二句的 explain，定位不到的话就看首句，往下看也能看到。第一个原因说了欧洲人一直住在一个地方，而美国人不是，对应答案 A；第二个原因说欧洲社会等级森严，换工作没那么容易，而美国刚好相反，分别对应 C 和 B 选项，所以 D 没有对应，答案是 D。

question_stem: Which of the sentences below best expresses the essential information in the highlighted sentence in the passage? Incorrect choices change the meaning in important ways or leave out essential information.
choices: tag: A
text: Because the West had more rivers and forests than the East, its soil was more productive.

tag: B
text: The fertile soils of the West drew farmers from regions with barren soils.

tag: C
text: Farmers living in western areas of the United States were more affected by soil erosion than farmers living in eastern areas.

tag: D
text: The soil in western areas of the United States was richer than soil in eastern areas.
answer_key: B
explanation: B 本句的主干就是罗列西部有很多吸引人之处，逻辑非常简单。所以答案是 B，A/C/D 的比较原文都没说。

question_stem: According to paragraph 3, what was the significance of the land law passed in 1820?
choices: tag: A
text: It granted government-supported loans to farmers.

tag: B
text: It provided farmland at an affordable price.

tag: C
text: It required banks to offer loans to farmers.

tag: D
text: It enabled farmers to sell their land for a profit.
answer_key: B
explanation: B 以1820做关键词定位至第二句，说1820年通过的新法案使农民可以用100USD 买土地，但是这里还没有把 significance 说明白，继续往下看。后面又说银行业的兴盛使得那些没钱的人能得到纸币贷款，所以是农民买得起土地，正确答案是 B。A 的 government-support，C 的 require 和 D 的 sell 都没说。

question_stem: The word "proliferation" in the passage is closest in meaning to
choices: tag: A
text: growth

tag: B
text: cooperation

tag: C
text: importance

tag: D
text: success
answer_key: A
explanation: A proliferation：扩张，扩散，增殖。A 是增长；B 是合作；C 是重要性；D 是成功。所以答案是 growth。

question_stem: Paragraph 4 suggests that turnpikes affected farmers by
choices: tag: A
text: making the price of grain uniform for both eastern and western farmers

tag: B
text: making western farm products more profitable than eastern farm products

tag: C
text: allowing farmers to drive their livestock across mountain trails

tag: D
text: allowing a greater number of farmers to sell their farm products in a commercial market
answer_key: D
explanation: D  以 turnpike 做关键词定位至后面两句，说改善运输状况的第一步是建公路，使得运输和农业的成本降低，所以答案是 D 鼓励人们卖东西。A 东西价格相等，B 的比较和 C 的 mountain trail 完全没提，都不选

question_stem: The word "superseded" in the passage is closest in meaning to
choices: tag: A
text: replaced

tag: B
text: reformed

tag: C
text: equaled

tag: D
text: increased
answer_key: A
explanation: A  supersede：代替。A 是取代；B 是改革；C 是与…相等；D 是增加。所以 A 的 replace 是答案。

question_stem: The word "diverted" in the passage is closest in meaning to
choices: tag: A
text: collected

tag: B
text: shifted

tag: C
text: transported

tag: D
text: sold
answer_key: B
explanation: B  divert: 转移，娱乐，使分心。A 是收集；B 是转移；C 是运输；D 是售卖。所以 B 的 shift 正确。

question_stem: Which of the following can be inferred from paragraph 5 about flatboats and keelboats?
choices: tag: A
text: They ceased to be used as soon as the first turnpikes were built.

tag: B
text: They were slower and more expensive to operate than steamboats.

tag: C
text: They were used for long-distance but not for regional transportation.

tag: D
text: They were used primarily on the Erie Canal.
answer_key: B
explanation: B 以两种船做关键词定位至第二句，说最终蒸汽船代替了原有的两种船，没有答案，往下看，说蒸汽船不仅快而且便宜，也就是说前面的两种慢而且不便宜，所以答案是 B，A 说反，C 和 D 没线索推得出来

question_stem: Paragraph 5 mentions that the Erie Canal led to a reduction in all of the following EXCEPT
choices: tag: A
text: the length of the route that goods from the West traveled across to reach eastern markets

tag: B
text: the cost of transporting freight

tag: C
text: the price of produce from western states

tag: D
text: the amount of produce from western states that was shipped on rivers
answer_key: C
explanation: C，EXCEPT 题，排除法。A 的 length of the route 做关键词定位至最后一句，a shorter route，正确，不 选；同时看到部分运输被分到 EC 上，所以河上运的东西就少了，所 以 D 的 shipped on river 有下降，D 也正确，不选；B 的 cost 和 freight 做关键词定位至倒数第二句，说从20下降到1，所以也下降了，不选；C 的 price 原文无对应，所以 C 错，选，不要自己想运输成本下降了价格就一定会下降