托福阅读经典加试:Modificationofweather试题及答案
托福阅读加试分为经典加试和非经典加试，一般情况下考生遇到的情况都是经典加试，即所加试的题目都是固定的几篇。这里小编为就为大家整理了托福阅读经典加试: Modification of weather试题及答案分享给大家，希望对大家托福备考有帮助。
托福阅读经典加试: Modification of weather试题及答案
阅读经典加试 7Title: Modification of weather
概述：modification of weather 多年来人们一直努力改变天气。最初是发现一战期间，降雨增多(可能与武器使用有关)，美国农业部开始试验。后来 1946 年，有个员工发现干冰能让 supercooled water become snow particles.文章给 supercool 下了定义就是低于零度但是还没有结冰。于是人们开始用 dry ice和 silver iodide来进行人工降雨。其原理就是 dry ice makes the moisture freeze into ice particles and the surrounding moisture freeze around it.也就是为降雨提供了凝结核。后来文章说有人担心这样下去会使地面水体的含银量增高，但是调查并没有显示这个说法。这种 cloud seeding 办法继续发展，用别的物质替代干冰。但是很多人 concern这种办法，会对 local 的环境带来影响，但是并无定论。
托福阅读推理题的答题技巧
一、 推理题的标志
推理题的题干中一般含有infer, imply, most likely, least likely, probably等词，分为有共性的推理题和无共性的推理题两大类。
二、 推理题的做法
对于无共性的推理题，也就是题干中无线索的，一般使用排除法，即根据各个选项的关键词回原文定位，通过排除法得出正确答案。
对于有共性的推理题，也就是题干中有线索的，建议考生可以先圈定题干中的关键词，根据关键词回原文定位，然后进行推理。推理题主要有下列思路：
1. 一般对比推理
ETS设计推理题的手段不多，根据两个事物的对比特征出题是其中之一。问其中一个事物的特征时，只要将与之形成对比的另一个事物的特征否定掉就可以了。
例如：
It should be obvious that cetaceans, whales, porpoises, and dolphins are mammals. They breathe through lungs, not through gills, and give birth to live young. Their streamlined bodies, the absence of hind legs, and the presence of a fluke and blowhole cannot disguise their affinities with land-dwelling mammals. However, unlike the cases of sea otters and pinnipeds (seals, sea lions, and walruses whose limbs are functional both on land and at sea), it is not easy to envision what the first whales looked like.
Which of the following can be inferred from paragraph 1 about early sea otters?
A. It is not difficult to imagine what they looked like.
B. There were great numbers of them.
C. They lived in the sea only.
D. They did not leave many fossil remains.
2. 时间对比推理
这种思路常被考到。在这种推理中，一般有两个形成对比的时间段，它们所具有的特征一般相反。当题干问一个时间段的特征时，只要将与之相反的时间段的特征否定掉就可以了。
例：
Basic to any understanding of Canada in the 20 years after the Second World War is the country’s impressive population growth….
…It appeared that Canada was once more falling in step with the trend toward smaller families that had occurred all through the Western world since the time of the Industrial Revolution.
It can be inferred from the passage that before the Industrial Revolution
(A) families were larger.
(B) population statistics were unreliable.
(C) the population grew steadily.
(D) economic conditions were bad.
3.集合概念推理
集合概念推理也可以称之为百分比推断，它指的是在一个集合中，包含两个相对的方面，共同构成一个大的集合。一方所占的比例减少意味着另一方所占比例的增加;反之一方所占的比例增加意味着另一方所占比例的减少。根据这一思路，可以由集合中一方的数量变化推断另一方的消减。
例：
A folk culture is small, isolated, cohesive, conservative, nearly self-sufficient group that is homogeneous in custom and race, with a strong family or clan structure and highly developed rituals. …Unaltered folk cultures no longer exist in industrialized countries such as the United States and Canada….
By contrast, a popular culture is a large heterogeneous group, often highly individualistic and constantly changing.
What does the author imply about the United States and Canada?
(A) They value folk cultures.
(B) They have no social classes.
(C) They have popular cultures.
(D) They do not value individualism.
托福阅读中需要留心的三大项
第一，托福阅读：词汇量是要害。
各位如果觉得托福阅读考试很难的话，请你必定要肯拿出时间来背单词。磨刀不误砍柴工，这句话一点都不假。即使你用一周时间，能把80%的单词都记住，那也是很值得的。
第二，托福阅读的做题次序。
现在还有人问，先看疑问再读文章，又说自己不习惯等等。其实，这个喜好在你自己。假设你觉得“先看疑问再读文章，并且找到答案就间断，再读下一个疑问”这样很习惯，那就坚持下去。如果你觉得全部文章读完再做心里踏实，那就读完好了。
第一题，一般都是主旨题。先不管。从第二题开始，看疑问，然后看是读第一段。不管有没有找到答案，把这一段读完再停。这样，如果词基本知道，语句结构比较清楚的话，答案差不多就出来了。接下来仍是这样，即使那一段很长，我也是读完一整段再做题。
可是这里要着重一下。如果你的托福阅读程度不是特别高的话，当你读完一段，有些疑问的答案你可能已经知道了，可是仍需要定位到原文，再看一遍。看看问题问的是不是的确是你得出的答案等等。总归一句话，托福阅读的答案都是从文章里来的，假设和文章对立了或者文章没有这些说法，那就必定不是准确答案!
第三，托福阅读解题技巧。
遇到不确定的问题，先从原文找到定位，然后把确定不对的选项排除。就算是瞎蒙，50%也比25%好。这个也是做主旨题的一贯准则。等你把文章通篇都读完了，再回过头看这个选项的时候，不准确的说法就可以排除了(如果你是最后做主旨题的话，一定不要忘了，还有一道题!)
推荐托福阅读中使用限时练习，把做过的阅读里出现的单词题的准确选项都摘录下来，尽管重复的几率不大，可是有些词是常常出现的。
托福阅读突破必背的介词短语
一、带-ing词尾的介词
barring：except，not including除……外
concerning：about，regarding论及，关于
excepting=except
failing：in default of因缺少……;在缺少……时
following：after in time;as a sequel to在……以后
including：if we include如果包括我;……包括在内
pending：during/until在……期间/直到……为止
regarding：about，concerning，in respect of
二、成语介词
according tas stated by/ in proportion根据……/依照……
ahead of：further forward in space or time sb/sth; ealier tan sb/sth; further advanced than sb/sth
along with：in addition to;together with另外，加之，还有
apart from：exceping，not considering; in addition to除……外/且莫说;除……之外尚有
as for：with regard to至于
as from：on and after(a specified time)从一特定时间开始
as of=as from
as regards：about，concerning至于，就……而论
as twith regard to关于，至于
because of：on account of，by reason
but for：without the help or hindrane etc.of假如没有……(帮助或障碍等);要不是
by means of凭借……的方法
due tbecause of由于
except for：not including，other than除了
in accordance with：in conformity to一致;依据
in front of：ahead of ，in the presence of在前面;当着……的面
in place of：in exchange for，instead of作为……的交换
in spite of：notwithstanding不管，不顾
instead of：in place of
in view of：considering由于，鉴于
with a view twuth the hope or intention of指望，考虑到
near tto or at a short distance from(in space，time，condition，or resemnlance)
next talmost，virtually几乎
on account of： beause of
on behalf of：in the interests of;as representative为了……的利益/代表
owing tbecause of由于
prior tbefore在前，居先
together with：as well as和，连同
up tuntil/below or equal to直到/不多于
in regard to=with regard tas concerns，in respect of
in that由于，因为
now that由于
托福阅读经典加试: Modification of weather试题及答案