老托福阅读试题及答案：PASSAGE27
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老托福阅读试题及答案：PASSAGE 27
The mineral particles found in soil range in size from microscopic clay particles to large boulders. The most abundant particles — sand, silt, and clay — are the focus of examination in studies of soil texture. Texture is the term used to describe the composite sizes of particles in a soil sample, typically several representative handfuls.
To measure soil texture, the sand, silt, and clay particles are sorted out by size and weight. The weights of each size are then expressed as a percentage of the sample weight. In the field, soil texture can be estimated by extracting a handful of soil and squeezing the damp soil into three basic shapes; (1) cast, a lump formed by squeezing a sample in a clenched fist; (2) thread, a pencil shape formed by rolling soil between the palms; and (3) ribbon, a flatfish shape formed by squeezing a small sample between the thumb and index finger. The behavioral characteristics of the soil when molded into each of these shapes, if they can be formed at all, provide the basis for a general textural classification. The behavior of the soil in the hand test is determined by the amount of clay in the sample. Clay particles are highly cohesive, and when dampened, behave as a plastic. Therefore the higher the clay content in a sample, the more refined and durable the shapes into which it can be molded.
Another method of determining soil texture involves the use of devices called sediment sieves, screens built with a specified mesh size. When the soil is filtered through a group of sieves, each with a different mesh size, the particles become grouped in corresponding size categories. Each category can be weighed to make a textural determination. Although sieves work well for silt, sand, and larger particles, they are not appropriate for clay particles. Clay is far too small to sieve accurately; therefore, in soils with a high proportion of clay, the fine particles are measured on the basis of their settling velocity when suspended in water. Since clays settle so slowly, they are easily segregated from sand and silt. The water can be drawn off and evaporated, leaving a residue of clay, which can be weighed.
1. What does the passage mainly discuss?
(A) Characteristics of high quality soil
(B) Particles typically found in most soils
(C) How a high clay content affects the texture of soil
(D) Ways to determine the texture of soil
2. The author mentions "several representative handfuls" in line 4 in order to show
(A) the range of soil samples
(B) the process by which soil is weighed
(C) the requirements for an adequate soil sample
(D) how small soil particles are weighted
3. The phrase "sorted out" in line 5 is closest in meaning to
(A) mixed
(B) replaced
(C) carried
(D) separated
4. It can be inferred that the names of the three basic shapes mentioned in paragraph 2 reflect
(A) the way the soil is extracted
(B) the results of squeezing the soil
(C) the need to check more than one handful
(D) the difficulty of forming different shapes
5. The word "dampened" in line 14 is closest in meaning to
(A) damaged
(B) stretched
(C) moistened
(D) examined
6. Which of the following can be inferred from the passage about a soil sample with little or no clay in it?
(A) It is not very heavy.
(B) It may not hold its shape when molded.
(C) Its shape is durable
(D) Its texture cannot be classified
7. The word "they" in line 21 refers to
(A) categories
(B) sieves
(C) larger particles
(D) clay particles
8. It can be inferred from the passage that the sediment sieve has an advantage over the hand test in determining soil texture because
(A) using the sieve takes less time
(B) the sieve can measure clay
(C) less training is required to use the sieve
(D) the sieve allows for a more exact measure
9. During the procedure described in paragraph 3, when clay particles are placed into water they
(A) stick to the sides of the water container
(B) take some time to sink to the bottom
(C) separate into different sizes
(D) dissolve quickly
10. The word "fine" in line 24 is closest in meaning to
(A) tiny
(B) many
(C) excellent
(D) various
11. All of the following words are defined in the passage EXCEPT
(A) texture (line 3)
(B) ribbon (line 10)
(C) sediment sieves (line 18)
(D) evaporated (line 25)
正确答案：DADBC BBDBA D
托福阅读怎么练?
有些考生则喜欢把文章一字不漏地细读之后再做题。这种方法仅适合于两种情况，其一，考生已具备相当的阅读水平，长期以来运用这种方法效果甚佳;其二，某一篇具体的文章是考生所熟悉的内容，细读文章并不会花太多的时间。一般来说，大部分考生采用细读文章方法，做题时间严重不足。考生不应该忘记，阅读理解测试速度和理解两个方面。
在做词汇题时，许多考生认为做不对题与自己的词汇量有关，认识单词能做对，不认识单词就会做错。事实上，那些认识的单词经常做错，不认识的单词反而能做对。原因是，做不认识单词时，考生会仔细研读词汇题的上下文，力求在上下文中突破。而做认识单词时，忽略上下文的重要性，往往是看一下上下文，便匆匆做出抉择。所以，做好词汇题关键在于透彻分析词汇题上下文的句子，有时候，个别词汇题也许需要在文章其他段落寻找线索。
做阅读题首先要花两三分钟时间扫描每篇文章头一两个句子，定位文章难易程度。一般来说，5篇文章中有2篇难度大一些，比方说：如果最后一篇文章难度大，且12-14道题，在这种情况下，按部就班做题就有可能因时间不够而做错好几道题，带来巨大的损失。因此首先定位文章难程度，同时目测文章的含金量(即题量分布)，有助于科学分配阅读部分的做题时间。
托福文章均由数个自然段组成，正确的阅读文章的方法应该是把文章首句先吃透，文章首句经常为文章主题。然后把首段的其他句子尽快略读，文章其他段落采取同样的方法阅读。各段落其他句子一般来说都是用来说明各个段落的主题句，没有必要每个句子理解难度大，而不涉及考题，在此句停留无疑是白白浪费时间。所以，采取"结构扫描"法，意味着以最快捷的方式了解文章大意，从而正确引导下一步做具体的题，而不至于出现大方向的理解错误。
托福阅读考试中的题材整理
一、印第安题材
1.白令海峡移民理论
2.印第安文化
3.印第安宗教观
4.印第安建筑业：大、先进。
5.印第安手工业：好。
6.社会组织结构：严密、分工细、凝聚力强。
7.农业先进：A. irrigation; B. maize, squash, bean, pea。
二、动植物题材(必考)
1.植物学题材(不多见)
a. 地衣、苔 、真菌、蘑菇最常见。
b. 树冠上方生物。
c. 植物在生态平衡中的作用。
2.动物学题材(90%以上)
a. 考普通动物为多。最近常考鸟类、蚂蚁、动物智能与灭绝(联系天文学与冰河理论)。
b. 考动物进化(evolution)。
c. 考动物的分类(classification)。
phyla(单数phylum) —门 class—纲 order—目 family—科 genus—属 species—种 carnivore/predator—食肉动物 herbivore—食草动物 omnivore—杂食动物
d. 动物的生活习性最为多见。
j群居(social animal)动物的习性
a) 蚂蚁：社会组织结构—等级制(caste)：交流方式—信息素—气味;生活来源;外来物种的有害性。
b) 蜜蜂：群居个性; “8”字舞;蜜蜂智能;防御;天敌—大黄蜂。
c) 大猩猩：智能：猩际关系
k迁徙 (migration )
野鸭、大雁：日照长短;辨别方向。
l伪装 (camouflage)、花拟态(mimicry )
三、考古学(archaeology)题材
1.文化(cultural ) 考古学
形态(physical)考古学(多见)
2.化石(fossil )
j 化石构成。化石比原物更沉重 (矿物质环境)
k 化石形成原因。 坚硬物质，迅速掩埋。
l 化石与动物的进化关系。
3.人的左右手
j 使用工具。 证据：敲击的划痕;手柄的形状。
k 牙齿上的划痕。
l 大脑左右半球的大小差别;趾骨的粗细差别。
m 作画时人像的方向
4.古代陶瓷的考古。
Clay, model, wheel (转盘 )， glaze, kiln
5.古代文字的考古。
四、美国历史题材
1.美国发展线索
j 发现美洲阶段
哥伦布(意)，为黄金、茶叶、香料
West/East Indian
影响：世界观变化;国家形势变化;(爱尔兰——土豆饥荒 )
k 英国定居阶段(English settlement )
1607第一个定居点Captain John S来源：www.examda.commith影响清教徒
1620五月花号
l 殖民时期(colonial era )
m 独立战争(American Revolution )
n 新的国家(new nation)考试大-全国最大教育类网站(www.Examda。com)：南北不均衡
o 南北战争(Civil War )
p 战后重建。 持续近100年。
q 西进运动 (Westward movement )
r 工业化大增长
s world war I & II
End ：1960
2.“大熔炉”：地理位置;民族融合1960’s;文化融合。
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