Forest fires have recently increased in intensity andextentin some forest typesthroughoutthe western United States. This recent increase in fires has resultedpartlyfromclimatechange the recenttrendtoward hot, dry summers andpartlyfrom human activities, forcomplicatedreasons that foresters came increasingly to understand about 30 years ago but whoserelativeimportance is still debated. Onefactoris the direct effect of logging, which often turns a forest into somethingapproximatinga huge pile of kindling (wood for burning): the ground in a logged forest mayremaincovered with branches and treetops, left behind when thevaluabletrunks are carted away; adensegrowth of newvegetationsprings up, further increasing the forest'sfuelloads; and the trees logged and removed are ofcoursethe biggest and most fire-resistant individuals, leaving behind smaller and moreflammabletrees.

Anotherfactoris that the United States Forest Service in the firstdecadeof the 1900s adopted thepolicyof firesuppression(attempting to put out forest fires) for theobviousreasonthat it did not wantvaluabletimberto go up in smoke, or people's homes and lives to be threatened. The Forest Service's announced goal became "Put out every forest fire by 10:00 A. M. on the morning after the day when it is first reported." Firefighters became much more successful at achieving that goal after 1945, thanks to improved firefighting technology. For a few decades theamountof land burnt annually decreased by 80 percent. That happy situation began to change in the 1980s,dueto the increasingfrequencyof large forest fires that wereessentiallyimpossible to extinguish unless rain and low winds combined to help. People began to realize that the United Statesfederalgovernment's fire-suppressionpolicywas contributing to those big fires and that natural fires caused bylightninghadpreviouslyplayed an important role in maintaining forest structure.

The natural role of fire varies withaltitude, treespecies, and forest type. To make Montana's low-altitude ponderosapineforest as an example, historical records, plus counts ofannualtree rings and datable fire scars on tree stumps, demonstrated that a ponderosapineforest experiences a lightning-lit fire about once adecadeunder natural conditions (i.e.., before firesuppressionbegan around 1910 and becameeffectiveafter 1945). Thematureponderosa trees havebarktwo inches thick and arerelativelyresistantto fire, whichinsteadburns out theunderstory- thelowerlayer- of fire-sensitive Douglas fir seedlings that have grown up since thepreviousfire. But after only adecade's growth until the next fire, those youngseedlingplants are still too low for fire tospreadfrom them into the crowns of the ponderosapinetrees. Hence the fire remains confined to ground andunderstory. As a result, many natural ponderosapineforests have a parklikeappearance, with lowfuelloads, big trees spaced apart, and arelativelyclearunderstory.

However, loggers concentrated on removing those big, old,valuable, fire-resistant ponderosa pines, while firesuppressionfor decades let theunderstoryfill up with Douglas fir saplings that would in turn becomevaluablewhen full-grown. Tree densities increased from 30 to 200 trees peracre, the forest'sfuelloadincreased by afactorof 6, and thegovernmentrepeatedly failed toappropriatemoney to thin out the saplings. When a fire finally does start in a sapling-choked forest, whetherduetolightningor human carelessness or (regrettably often)intentionalarson, thedense, tall saplings (young trees) may become a ladder that allows the fire to jump into the crowns of the trees. Theoutcomeis sometimes an unstoppable inferno.

Foresters nowidentifythe biggest problem in managing Western forests as what to do with those increasedfuelloads that built up during theprevioushalf century ofeffectivefiresuppression. In the wetter eastern United States, dead trees rot away more quickly than in the drier West, where more dead treespersistlikegiantmatchsticks. In anidealworld, the Forest Service wouldmanageandrestorethe forests, thin them out, and remove thedenseunderstoryby cutting or by controlled small fires. But nopoliticianor voter wants to spend what it wouldcostto do that.

Questions:
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: Climate change caused by human activity is the main reason for the increase in fires over the past 30 years.

tag: B
text: While human activity is definitely considered a factor, foresters are still debating whether climate plays a role in the recent increase in fires.

tag: C
text: For complicated reasons, over the past 30 years there has been an increase in the number of fires that take place during hot, dry summers.

tag: D
text: Both climate change and human activities are responsible for the recent increase in forest fires, although the contributions of those factors are still not agreed on.
answer_key: D
explanation: 【题目翻译】下面哪句话最能表达文章中突出显示的句子中的基本信息？错误的选择会以重要的方式改变意义，或者遗漏重要的信息。
A：人类活动引起的气候变化是近30年来火灾增加的主要原因。

B：虽然人类活动肯定被认为是一个因素，但森林学家仍在争论气候是否在最近的火灾增加中起作用。

C：由于复杂的原因，在过去的30年里，在炎热干燥的夏季发生的火灾数量有所增加。

D：气候变化和人类活动都是导致最近森林火灾增加的原因，尽管这些因素的作用仍未达成一致。

【判定题型】：根据题目问法，题目要求选择和高亮句意思逻辑都最为接近的句子，故判断本题为句子简化题。

【句子分析】题根据题干找到高亮部分：This recent increase in fires has resulted partly from climate change (the recent trend toward hot, dry summers) and partly from human activities, for complicated reasons that foresters came increasingly to understand about 30 years ago but whose relative importance is still debated. 本句大意是：最近森林火灾的增长一部分是气候变化（夏天变得更干更热）和人类活动的原因，虽然这些复杂原因谁更重要还在争论中。

【选项分析】
A.选项 A 说人类活动导致气候变化，错误；
B.选项 B 说森林学家还在争辩气候变化算不算一个导致森林大火的原因，错误，只是在争辩谁更重要；
C.选项 C 说在夏天的森林大火增多，本句没有具体说到在哪个季节森林大火多，错误。
D.符合文意，正确。

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

tag: B
text: surrounding

tag: C
text: resembling

tag: D
text: providing
answer_key: C
explanation: 【题目翻译】文中“approximating”与下列哪一个意思最相近？
选项 A 的意思是包含，
选项 B 的意思是环境，
项 C 的意思是相似，
选项 D 的意思是提供。

【判定题型】：题目要求选出与高亮单词意思最接近的选项，故判断本题为词汇题。

【关键词定位】：根据关键词“approximating”,定位到原句“One factor is the direct effect of logging, which often turns a forest into something approximating a huge pile of kindling (wood for burning)”。

【词汇解析】：词汇“approximating”的意思是“接近”,带入到原句中，原句的意思是“有一个直接影响一片森林被砍伐成类似于一堆燃烧的木头堆的原因”。

【选项分析】
选项 A 的意思是包含，不符，错误
选项 B 的意思是环境，不符，错误
选项 C 的意思是相似，同义替换，正确
选项 D 的意思是提供。不符，错误

question_stem: All of the following are mentioned in paragraph 1 as consequences of logging that can promote forest fires EXCEPT
choices: tag: A
text: Fires are accidentally started by loggers.

tag: B
text: Pieces of flammable wood are left behind in the forest.

tag: C
text: There is a dense growth of new plants that act as fuel for fire.

tag: D
text: The most fire-resistant trees are removed by the loggers.
answer_key: A
explanation: 【题目翻译】第1段中提到的以下所有情况都是由于伐木会引发森林火灾，除非
A：火灾是伐木工人意外引发的。

B：森林里留下了几块易燃的木头。

C：有大量的新植物作为燃烧的燃料。

D：最耐火的树是由伐木工人砍伐的。

【判定题型】：根据题干中出现的大写“EXCEPT”/"NOT" 等其他明显表示否定的词，可以判定本题为否定事实信息题，需要找出与原文信息不符的那个答案。

【关键词定位】：根据题干关键词“ forest fires”,可以将出题范围锁定在 Passage 1 。

【选项分析】
选项 A 在原文中没有对应依据，错误。选择 A。
选项 B 对应原文中的 leaving behind smaller and more flammable trees，正确；
选项 C 对应原文中的 a dense growth of new vegetation springs up, further increasing the forest's fuel loads，正确；
选项 D 对应原文中的 the trees logged and removed are of course the biggest and most fire-resistant individuals，正确。

question_stem: What can be inferred from paragraph 2 about forest-fire suppression before 1900?
choices: tag: A
text: It was more effective than afterward because there were fewer fires to suppress in most regions.

tag: B
text: There was no official program of forest-fire suppression in the United States.

tag: C
text: Forest-fire suppression was practiced more for the purpose of protecting homes than for protecting forests.

tag: D
text: The Forest Service had rules to control forest fires, but the rules were ignored.
answer_key: B
explanation: 【题目翻译】关于1900年以前的森林灭火，从第2段可以推断出什么？
A：这比后来更有效，因为在大多数地区要扑灭的火灾更少。

B：美国没有官方的森林灭火计划。

C：森林灭火更多是为了保护家园，而不是为了保护森林。

D：森林管理局有控制森林火灾的规则，但这些规则被忽略了。

【判定题型】：根据题干中出现的关键词“imply”/“infer”/“suggest”等其他表示推断的词，判定本题为推理题。

【关键词定位】：根据关键词“forest-fire suppression”,定位到 Passage 2。

【逻辑分析】段落说的是：另一个因素。美国林业局在二十世纪头十年采取的灭火政策。

【选项分析】
选项 A 涉及到原文中的 Firefighters became much more successful at achieving that goal after 1945, thanks to improved firefighting technology. 说明其实灭火是越来越容易了，因为灭火技术在进步，错误；
选项 B 涉及到原文中的 Another factor is that the United States Forest Service in the first decade of the 1900s adopted the policy of fire suppression，说明1900年以前还没有官方的行动，正确；选择 B。
选项 C 涉及到原文中 it did not want valuable timber to go up in smoke, or people's homes and lives to be threatened，并没有说灭火行动更多是为了保护家庭或是森林，错误；
选项 D 是说灭火的规则被忽视了，在原文中没有提及，错误。

question_stem: Why does the author include the quotation "Put out every forest fire by 10:00 A. M. on the morning after the day when it is first reported"?
choices: tag: A
text: To suggest that the Forest Service's goals were unrealistic and ultimately unattainable.

tag: B
text: To demonstrate how seriously the Forest Service took their responsibility of fire suppression.

tag: C
text: To support the idea that fire-suppression techniques are most effective early in the day.

tag: D
text: To provide an example of the new methods that resulted in successful firefighting after 1945.
answer_key: B
explanation: 【题目翻译】为什么作者引用了“在第一次报告的第二天早上10:00之前扑灭森林大火”这句话？
A：建议林业局的目标不现实，最终无法实现。

B：为了证明林业局对灭火责任的重视程度。

C：支持灭火技术在早期最有效的观点。

D：举例说明1945年后成功灭火的新方法。

【判定题型】：根据题干问法“why ……  include ”，题目询问“xxxxxx”(文章引用内容)的修辞目的，可以判断本题为修辞目的题。

【关键词定位】根据关键词“Put out every forest fire”,定位到 Passage 2 第2句，原句为"Put out every forest fire by 10:00 A.M. on the morning after the day when it is first reported."。

【引用内容分析】本题先看给出的句子：这句话的意思是：我们在每场森林大火被首次报道的第二天早上10点前灭掉它们。这个命令显示了灭火团队对于灭火的负责。

【选项分析】
A.选项 A 说为了说明灭火队的目标是不现实的，不符题意
B.符合原文，正确
C.选项 C 的意识是为了支持灭火措施在现在越来越有效了，不符题意
D.选项 D 的意思是给出成功的灭火方法的例子，不符题意

question_stem: According to paragraph 3, all of the following have been used to determine the frequency of forest fires under natural conditions in Montana's ponderosa pine forests EXCEPT
choices: tag: A
text: recent records of fire-suppression efforts in the region

tag: B
text: historical documents

tag: C
text: examination of tree rings on burned trees

tag: D
text: the dating of scars on remaining stumps of fire-damaged trees
answer_key: A
explanation: 【题目翻译】根据第3段，以下所有内容均被用于确定蒙大拿州黄松森林自然条件下森林火灾的频率，除了
A：该地区灭火工作的最新记录

B：历史文献

C：烧毁树木的年轮检查

D：火灾受损树木残桩上疤痕的年代测定

【判定题型】：根据题干中出现的大写“EXCEPT”/"NOT" 等其他明显表示否定的词，可以判定本题为否定事实信息题，需要找出与原文信息不符的那个答案。

【关键词定位】根据题干关键词 determine the frequency 可将出题范围锁定在 Passage 3。

【选项分析】
A.只有选项 A 没有原文中的依据。选项 A。
B.选项 B 对应 historical records，不选。
C.选项 C 对应 counts of annual tree rings，不选。
D.选项 D 对应 datable fire scars on tree stumps，不选。

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

tag: B
text: Therefore

tag: C
text: Certainly

tag: D
text: In particular
answer_key: B
explanation: 【题目翻译】文中“Hence”与下列哪一个意思最相近？
选项 A 是后来，
选项 B 是因此，
项 C 是当然的确定的，
选项 D 是尤其的。

【判定题型】：题目要求选出与高亮单词意思最接近的选项，故判断本题为词汇题。

【关键词定位】：根据关键词“Hence”,定位到原句 Hence the fire remains confined to ground and understory.。

【词汇解析】：词汇“Hence”的意思是“因此”,带入到原句中，原句的意思是“：因此大火就被控制在了地面，烧不到树冠上，破坏性也被控制了。”

【选项分析】
选项 A 是后来，不符，错误
选项 B 是因此，同义替换，正确
项 C 是当然的确定的，不符，错误
选项 D 是尤其的。不符，错误

question_stem: In paragraph 3, what is the author's purpose in describing the natural cycle of fires in ponderosa pine forests?
choices: tag: A
text: To emphasize the importance of replanting seedlings after a forest fire.

tag: B
text: To argue for increasing the effectiveness of laws to suppress forest fires.

tag: C
text: To describe how fire affects a typical ponderosa pine forest in the absence of human intervention.

tag: D
text: To explain the long-lasting damage that once occurred in the ponderosa pine forests of Montana before fires were controlled.
answer_key: C
explanation: 【题目翻译】在第3段中，作者描述黄松松林火灾自然循环的目的是什么？
A：强调火灾后植苗的重要性。

B：为提高法律对抑制森林火灾的效力而争论。

C：描述在没有人为干预的情况下，火是如何影响一个典型的黄松森林的。

D：解释在控制火势之前，蒙大拿州的黄松森林曾经遭受的长期破坏。

2、【判定题型】：根据题干问法“what is the author's purpose”，题目询问“xxxxxx”(文章引用内容)的修辞目的，可以判断本题为修辞目的题。

【关键词定位】：根据关键词“natural cycle”,定位到第三段的后半段，原句为“But after only a decade's growth until the next fire, those young seedling plants are still too low for fire to spread from them into the crowns of the ponderosa pine trees. @@@@Hence the fire remains confined to ground and understory. @@@@As a result, many natural ponderosa pine forests have a parklike appearance, with low fuel loads, big trees spaced apart, and a relatively clear understory.”。

【引用内容分析】每次新的火起来后，都会因为小树太矮了而烧不到大树的树干，因此火焰被控制在了地面，破坏性也被控制了。作者形容这个过程是为了向我们说明 ponderosa 树在着火时候的情况，当然也是在无人干预的情况下。

【选项分析】
A.未提及火灾后植苗，故错误。
B.没有要做争论，故错误。
C.符合文意，正确；
D.是要说明火和黄松林的关系，不是要说破坏，故错误。

question_stem: According to paragraph 4, why is the human preservation of Douglas fir sapling trees a threat to the ponderosa pine forest?
choices: tag: A
text: The presence of many sapling trees makes it more difficult for firefighters to reach the source of a forest fire.

tag: B
text: Douglas fir saplings are expensive to maintain, leaving little government money for forest-fire suppression.

tag: C
text: Saplings compete for space with the larger and more valuable fire-resistant trees.

tag: D
text: Dense areas of tall sapling trees can spread fire to the crowns of larger, fire-resistant trees.
answer_key: D
explanation: 【题目翻译】根据第4段，为什么人类保护道格拉斯冷杉幼树会对黄松森林构成威胁？
A：许多幼树的存在使消防员更难到达森林火灾的源头。

B：道格拉斯冷杉树苗的维护费用很高，几乎没有政府的资金用于森林灭火。

C：树苗与更大、更有价值的防火树争夺空间。

D：高树苗密集的地区可以把火蔓延到较大的耐火树的树冠上。

【判定题型】：题目问的是文章中的具体细节信息，故根据题目问法可以判断本题为事实信息题。

【关键词定位】本题根据 Douglas fir sapling trees 定位到原文中这里：When a fire finally does start in a sapling-choked forest, whether due to lightning or human carelessness or (regrettably often) intentional arson, the dense, tall saplings young trees) may become a ladder that allows the fire to jump into the crowns of the trees. 意思是“这种新种的树木容易着火，一旦大火燃烧起来，这种树的树苗足够高，油脂足够多，很容易把大火引到大树的树冠上，进而酿成森林大火”。

【逻辑分析】可知，新树的树木树苗高，容易着火，容易酿成森林大火。

【选项分析】
A.没有提到关键点：高树苗密集。故错误。
B.维护费用不是重点，故错误。
C.争夺空间错误。
D.符合文意，正确。

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

tag: B
text: surprisingly

tag: C
text: probably

tag: D
text: extremely
answer_key: A
explanation: 【题目翻译】文中“regrettably”与下列哪一个意思最相近？
选项 A 是不幸的，
选项 B 是惊奇的，
选项 C 是可能的，
选项 D 是极其的。

【判定题型】：题目要求选出与高亮单词意思最接近的选项，故判断本题为词汇题。

【关键词定位】：根据关键词“regrettably”,定位到原句“When a fire finally does start in a sapling-choked forest, whether due to lightning or human carelessness or (regrettably often) intentional arson, the dense, tall saplings (young trees) may become a ladder that allows the fire to jump into the crowns of the trees. ”。

【词汇解析】：词汇“regrettably”的意思是“不幸的”,带入到原句中，原句的意思是“当一场大火最终在砍伐过森林里燃烧起来时，不管是因为闪电还是人类的不小心或者（很不幸经常发生的）故意纵火，枝叶浓密还高的小树会成为火势烧到树冠的梯子。”。

【选项分析】
选项 A 是不幸的，同义替换，正确
选项 B 是惊奇的，不符，错误
选项 C 是可能的，不符，错误
选项 D 是极其的。不符，错误

question_stem: What does paragraph 5 describe as a solution to the fires in Western forests?
choices: tag: A
text: The careful management of forests to reduce the buildup of fuel loads.

tag: B
text: The preservation of a dense understory.

tag: C
text: The occasional flooding of western forests to make them as wet as those in the East.

tag: D
text: A return to the effective methods of fire suppression of the previous half century.
answer_key: A
explanation: 【题目翻译】第5段描述了如何解决西部森林火灾？
A：对森林的精心管理，以减少燃料负荷的积累。

B：保护茂密的下层建筑。

C：西部森林偶尔泛滥，使它们像东部森林一样潮湿。

D：回到上半个世纪有效的灭火方法。

【判定题型】：题目问的是文章中的具体细节信息，故根据题目问法可以判断本题为事实信息题。

【关键词定位】本题根据题干中关键词 solution 定位到这一句：In an ideal world, the Forest Service would manage and restore the forests, thin them out, and remove the dense understory by cutting or by controlled small fires. 
意思是“一种理想的解决办法是削薄或者砍伐这些含油量高的树木的密度，并且严密控制小型火灾的发生”。

【逻辑分析】可知，防火灾的方法是：削薄或者砍伐这些含油量高的树木的密度。还有要控制小火灾。

【选项分析】
A.管理西部森林时面临的最大的问题在于如何处理这些不断增加的燃料总量，这些燃料是在过去的半个世纪间由于有效的灭火政策而积聚起来的。是防火的办法，故正确。
B.防火灾的方法是：削薄或者砍伐这些含油量高的树木的密度。还有要控制小火灾。
C.不符文意，错误。
D.未提到回到上世纪的灭火方法，故错误。

question_stem: According to paragraph 5, people in the United States would probably not support the described forest-management and restoration techniques because they
choices: tag: A
text: think that the use of small, controlled fires may be too dangerous.

tag: B
text: do not want to spend money on the expensive process of managing forest understory.

tag: C
text: distrust the Forest Service due to the harmful fire-suppression techniques of the past.

tag: D
text: do not want politicians involved in forest management.
answer_key: B
explanation: 【题目翻译】根据第5段，美国人民可能不支持所述的森林管理和恢复技术，因为他们
A：认为使用小规模、可控的火灾可能太危险。

B：不要把钱花在管理森林下层林的昂贵过程上。

C：由于过去的有害灭火技术，不信任林业局。

D：不要让政治家参与森林管理。

【判定题型】：题目问的是文章中的具体细节信息，故根据题目问法可以判断本题为事实信息题。

【关键词定位】：根据关键词“not support”,定位到 Passage 5 ，原句为“But no politician or voter wants to spend what it would cost to do that. ”，意思是“没有政治家或者选民愿意去花费这个解决办法需要的钱”。

【逻辑分析】所以可知关键还是这个办法花费高。

【选项分析】
A.与火灾是否太危险无关，故错误。
B.符合愿意，故正确。
C.与是否信任林业局无关，故错误。
D.是没有政治家或选民愿意参加，故选项错误。