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托福口语背景知识补充

时间：2022年12月20日

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以下是小编为大家准备的托福口语背景知识补充，本文共7篇，仅供参考，欢迎大家阅读。本文原稿由网友“Mångata”提供。

篇1：托福口语背景知识补充

托福口语背景知识补充这些常见词汇背后的故事你知道吗?

托福口语10个常用俗语词汇典故介绍

1. nerd和jock是美国学生常用的两个俗语。nerd的意思和汉语中的“书呆子”类似。这类人聪明勤奋，但却过于保守严肃，在校园里颇让人瞧不起。 jock则恰恰相反。他们魁梧帅气，很受女孩子们的欢迎，尤其擅长American football和basketball等各种体育运动。当然，校园中也不乏漂亮的girl jocks。

2. egghead这个词在1952年的美国总统大选中被首次使用。当时的竞选双方分别是二战盟军总司令艾森豪威尔和书生气十足的伊利诺伊州州长史蒂文森。史蒂文森精心准备的竞选演讲文字华丽晦涩，只有和他一样的知识分子才会感兴趣。因此对手取笑他说：Sure, all the eggheads love Stevenson. But how many eggheads do you think there are。 egghead的意思，就是指书生气很足的知识分子。

3. hick和city slicker这两个词的意思在各种语言中一定都能找到对应的词，它们分别是城里人和乡下人对对方的贬称。hick的意思是“乡巴佬，土包子，”而 slick字面意思是“圆滑的，油滑的”，因而city slicker也就是乡下人眼中的“城里老油子，打扮光鲜，老于世故却不可信的城里滑头”。

4.turkey(火鸡)，shrimp(虾)和crab(螃蟹)这三种动物在美国人眼中会是什么人呢?turkey是美国人在 Thanksgiving Day和Christmas Day家家都要吃的食物。但是，活的火鸡样子难看，行动又笨拙，所以turkey就用来形容那种愚蠢无用的人。而那种雇用了这些turkey，又不能开除他们的政府或商业机构就被称作turkey farm。shrimp常被用于指代那些个子矮小的人或无足轻重的小人物。请看下面的句子：You may call Napoleon a little shrimp. But for a shrimp, he certainly made the rest of Europe tremble。而crab因为长相丑陋凶恶，常被用来指那些性格暴躁、脾气很坏的人。

5. baby boomer, yuppie(雅皮士)， dink(丁克)，sandwich generation这四个词反映了美国经济和社会变化。二战结束后的二十年内，美国人口激增，那个时期出生的人在美国被称作baby boomers，因为boom有激增、暴涨之意。yuppie(雅皮士)(young urban professionals)是指生活在大城市、受过高等教育、生活富裕的成功职业人士。dinks (double income, no kids)是指那些有很好的工作和收入，但是不要孩子的夫妇。sandwich generation则恰恰相反，他们是既要赡养老人，又要抚养下一代，像三明治一样被夹在中间的经济负担较重的一群人。

6. couch potato和mall rat是两个和美国人生活习惯有关的俗语。couch potato指一有时间就坐在沙发上看电视的人，一声不吭，一动不动，就像一个圆滚滚的土豆。而mall rat当然不会是购物中心的真老鼠，而是指没事儿老喜欢到mall(大商场)里去逛的人。

7. backseat driver, wheeler-dealer, free-wheeler, fifth wheel是四个和汽车有关的常用习语。backseat driver坐在汽车后排，却不停地对前面开车的人指手画脚，因此是指那些自己不在岗位上，但是却喜欢给在位的人提供人家不需要的意见的人。 wheeler-dealer精明能干，是那种善于运用权利和财势在政治或商业活动中为所欲为，独断独行的人。free-wheeler喜欢自由，不受约束，是指那些不愿意遵守自己工作单位的规章制度，想怎么做就怎么做的人。而fifth wheel的意思则很好猜出。一辆汽车只有四只轮子，那么，fifth wheel当然是多余的、不受欢迎的人了。

8. green thumb和all thumbs也是两个很有意思的俗语。green thumb指善于养花种草的人，这些人总是能把花园收拾得绿色怡人，养出来的花草光亮健康，羡煞那些费了很多劲儿，种出来的花草蔬菜却总是半死不活的人。所以，green thumb就是那些很会养花种草的人。如果说一个人是all thumbs会是什么样呢?想想看，拇指虽好，可要是十个指头都长成短短粗粗的拇指，干起活来肯定很难受。因此all thumbs便是形容一个人笨手笨脚。

9.penny-pincher和cheapskate都是指花钱很小心、吝啬的人。penny是一美分，pinch意为“捏”，顾名思义，penny-pincher就是那些连一分钱都要在手里捏得紧紧的、舍不得花出去的人。cheapskate则是万事以省钱为本，越省越好，请客最多带你去MacDonald。这种人往往不受欢迎，尤其令他们的女朋友反感。从这个意义上说，cheapskate比penny-pincher更贬损。

10. spring chicken和lame duck是指春天孵出的小鸡和瘸腿的鸭子吗?当然不是，读一读下面这两句话，猜猜它们的意思吧。(1)The woman said,over forty, so I’m not a spring chicken any more。(2)The governor of our state ended up as a lame duck when he lost the election. He still has six weeks left in office but there’s nothing to do except to pack up his papers。实际上，spring chicken意为“年轻人，缺乏经验的人”，lame duck是指“竞选连任失败、即将卸任的官员”，也用来指“不中用的人”。任何美国官员——从市长、州长、参议员到总统——都有可能因无能而被称为 lame duck。

以上就是托福口语词汇中的10个比较常用的俗语词汇的典故背景介绍。托福口语考察的是大家的表达能力，所以各位同学在练习的时候，需要主动积累和运用一些美国俗语及俚语，这样才能让自己的托福口语说得更地道更有美国味。最后小编预祝大家顺利通过考试拿到理想成绩。

托福口语机经预测

1. Talk about the advantage and disadvantage of being active on social

media.

2. Should students be required to evaluate their professors at the end of

the semester?

3. Your professor asks you to help him with his research project, but on

that day you have promised your sister to attend her birthday party. How will

you choose?

4. Which of the following people can give most useful help in your future

career direction?

1) Teachers

2) Families

3) Friends

5. How should parents teach their kids to work with others?

6. If a foreign teacher comes to your country to teach high school student,

what suggestions will you give him for preparation?

7. Which of the following has the greatest impact on students’ life?

1) electronic books

2) smart phones

3) online courses

8. Suppose your friend is going to a job interview. What suggestions do you

have for him?

9. If your university is going to invite someone to give a speech, who do

you think they should invite? A businessman, a scientist or a politician?

10. Your friend has to work a lot. Please suggest a hobby that can help him

spend his weekend in a more delightful way. Explain why. Please include details

and examples in your explanation.

11. A lot of experienced and inexperienced climb mountains every year,

which one of the following adjectives would you use to describe this experience?

Adventurous, frightening or foolish?

托福口语机经预测

1. If your friend wins an award from his achievement, how would you

celebrate for him?

2. What do you think are the common mistakes when parents raise their

kid?

3. If a foreign teacher comes to your country to teach high school student,

what suggestions will you give him for preparation?

4. If your university is going to invite someone to give a speech, who do

you think they should invite? A businessman, a scientist or a politician?

5. Which of the following attributes would you consider the most valuable

in your roommates?

1) being friendly

2) being quite

3) has a good hygiene habit

6. Which of the following do you think is the most important quality for an

employee?

1) Performance during the interview

2) Previous work experience

3) Education background

7. The university international office is going to hold a social event.

Which one of the following choices do you think is the best?

1) international food fair

2) international music festival

3) international film festival

8. Which of the following three behaviors would you consider the most

negative for kids?

1) Being selfish

2) Saying impolite things

3) Speaking loudly in public

9. Talk about the advantage and disadvantage of being active on social

media.

10. Your degree requires you to take one course, which one would you

choose?

1) Energy and environment

2) Health and nutrition

3) Solar system

托福口语怎样训练表述能力

托福独立口语

根据熟悉的话题进行论述，如描述一个熟悉的地方或谈论一段个人经历;

用简单明了的语言说明一种观点或偏好，并用逻辑的语言对原因进行阐述;

提出一项建议并用合理的解释规劝别人接受这个建议;

罗列出ETS常出现的热门话题，并针对这些话题做出一分钟的回答。用考试的真实境况，选择一道题，准备1分钟后，用自己的语言表达观点和阐述原由，从而达到提高口头表达能力的目的。

托福综合口语

平时的教科书就是不错的教材，对每个章节在结尾处提出的问题给予口头回答;

选读一篇长短适中的文章，提炼出纲领性的要点，在提炼要点的基础上锻炼用口头表述来进行总结;

针对一些相同话题的阅读和听力材料进行有效练习。并针对这些材料做笔记和做以下准备：学会口头提炼和总结这些阅读和听力材料;在此基础上口头表述重要的信息，并解释其中相互之间的关联;针对阅读和听力材料中的观点进行阐述;对其中提出的某个问题，阐述一种解决问题的方案，并给出相对应的理由。

新托福的口语考试采用人机对话的方式，考生无法和真正的考官交流，所以考生的成绩不会受到一些人为主观印象的影响。但对考生来说，完全要靠语言能力去应付，没有肢体语言的辅助，就需要练就一套真功夫。

篇2：托福阅读背景知识材料补充

托福阅读背景知识材料补充站着办公的风险你知道吗?

托福阅读背景知识文章：站着办公的风险

A new study says that standing up at your desk doesn’t actually decrease your risk of death-by-office, unless you’re physically active otherwise.

新研究表明：除非经常锻炼，否则站着工作也不会降低猝死风险。

After several studies asserted that sitting at work all day is slowly killing us, researchers at the University of Exeter and University College London took another look at the claims. The Washington Post reports:

此前，已有多项研究表明，久坐会慢慢地致人死亡。但埃克塞特大学和伦敦大学学院的几位研究员却从另一角度进行了研究。华盛顿邮报报道：

Researchers tracked 16 years’ worth of health data from 5,132 people in the Whitehall II study cohort. Participants reported their total time sitting and how long they sat during four different situations: at work, watching television, leisure time and non-television leisure time. Researchers also tracked time spent walking daily and on physical activity.

此次研究的调查对象来自白厅二级定群研究，共5132人。研究人员对他们长达的健康数据进行了跟踪。调查对象需汇报他们坐下的总时长，以及在四种不同场合——工作、看电视、业余活动，以及不看电视的业余活动——分别坐下的时长。研究人员还跟踪调查了他们每日步行和运动的时长。

After controlling for a number of factors, including diet and general health, researchers found the overall mortality risk for these participants wasn’t influenced by how long they sat or by the kind of sitting. And the researchers cautioned that too much emphasis on not sitting shouldn’t take the place of promoting physical activity.

研究人员在控制了包括饮食、整体健康在内的许多变量后，发现：调查对象的总死亡率不受久坐时间和坐姿的影响。研究人员告诫称，人们不应过份强调久坐的风险，而忽视强调运动的重要。

What’s particularly interesting about the study, published in the International Journal of Epidemiology, is that researchers didn’t just focus on sitting during the workday, but factored in all kinds of sitting-specific data as well as rates of physical activity. Their conclusion was that “sitting time was not associated with all-cause mortality risk.” Basically, more elements are in play than just whether you’re sitting down at work, and your levels of physical activity are the greatest health indicator.

这项研究发表在《国际流行病学杂志》上。其中特别有趣的是，研究员没有只研究人们在工作时的久坐情况，还考虑到了各种相关数据和运动频率。其结论是“久坐与全因死亡率无关”。总而言之，影响健康的元素很多，不仅仅在于是否在工作时久坐。最能体现健康状况的是锻炼情况。

So what does this all mean? It appears that the act of working while standing up—which has become a trendy thing to do, especially in tech offices—doesn’t help your health, if you’re not actually exercising otherwise. If you never make it to the gym, you might as well just sit down. This is good news for the makers of treadmill desks, however.

所以这到底意味着什么?现在流行站着办公，科技公司尤为突出。但是如果不锻炼，站着工作也似乎没什么用;如果永远都不去健身，还不如就坐着呢。这对跑步机办公桌的生产商来说，可是个好消息。

The last office where I worked jumped on the standing desk trend hard, installing desks that could be raised for all workers. They also had a treadmill desk, and a bike desk. While the option to stand is certainly nice as a change in the middle of a monotonous workday, this research suggests it’s not the cure-all that adherents would like to claim.

我之前工作的地方勉强跟上了站立式办公桌的潮流，装上了可随意调节高度的桌子。此外，还有一张跑步机办公桌和一张自行车办公桌。当然，在乏味的工作之余能站着工作也是个不错的选择，但研究表明，站着工作并不是所谓的万灵丹。

“Our study overturns current thinking on the health risks of sitting and indicates that the problem lies in the absence of movement rather than the time spent sitting itself,” study author Melvyn Hillsdon of the University of Exeter said in a statement. “Any stationary posture where energy expenditure is low may be detrimental to health, be it sitting or standing.”

“我们的研究推翻了当下人们对久坐危害的认知，并指出危害健康的原因在于缺乏锻炼，而不是久坐，”来自埃克塞特大学的研究作者梅尔文·希尔斯顿在一份声明中说道。“身体静止不动，能量消耗就低，从而危害健康，不管是坐着还是站着都一样。”

The takeaway here is companies that truly want to assist worker health should invest money in options like free exercise classes and gym reimbursements. They should encourage employees to go outside and actually walk around, not simply stand up at their computers. And maybe it means that everyone who insists that standing up is the only way to work can climb down off their high desk.

这表明，真正关心员工健康的公司应该把钱花在购买免费运动课程和报销健身费用上。公司应鼓励员工走出办公室，四处走走，而不是只在电脑前站着工作。或许这意味着那些坚信“站着是唯一解决办法”的人终于能从高高的桌子上爬下来了。

托福阅读素材：如何帮助一个应届生找到工作

You probably know someone who's graduating from college this year. And what would Amazon or Pinterest suggest you give this brave soul who's walking over coals to the hellish world of job searching? A pen. (A nice pen, but a pen.) Or a mug with an inspirational quote printed on it. Or a business card holder.

You know what would be more helpful than those gifts? A job. Preferably a job with a desk, where this graduate can use her pen, drink from her mug and store her business cards.

Luckily, you – yes, you – can help give that greatest gift of all. Here's how to help a newbie job seeker land a job:

1. Start by looking within your company. Don't see any entry-level jobs listed for your company? That may be because those positions often go unlisted and are filled by internal referrals, says Brian Krueger, founder and CEO of CollegeGrad.com, an entry-level job search site, and author of “The College Grad Job Hunter.” That's where you come in, passing the job seeker's résumé to your human resources department. “If they're a good person for your company, go ahead and refer them internally,” he says. “And you may make a nice little employee referral bonus for making that connection.”

Even if there isn't an open and relevant position available for your contact right now, this referral may help both the recent grad and HR department in the future. Keep in mind that entry-level positions often have high turnover, Krueger says. And consider how larger companies sometimes hire numerous entry-level employees at once, and how usually a few of them will back out of the program just before it begins, he adds. Where do you think the HR team will turn in those situations, when they've got to do some speedy hiring? “If you've got an employee referral sitting there, waiting, that person may be given first consideration and very little competition for that entry-level position if and when it comes up,” Krueger says.

2. Reach out to your network. Share the job seeker's résumé with folks outside your company, too. If there's not much crossover between what you do and what the new grad wants to do, remember: “You may have other connections outside of your job type and industry,” Krueger says. Is there anyone in your book club or yoga class who could help? What about neighbors or family members? Shoot them the résumé, and encourage them to pass it along to whomever may be interested.

In fact, that's where things get interesting. “It's not necessarily who you know, it's who they know,” Krueger says. Maybe there's not much cooking among your connections or even your connections' connections. But the more folks forward the referral, the more eyes (and potential employers) will see it. “Networking is a numbers game,” Krueger says, and it's in those third-level contacts and beyond “where the numbers explode.”

Even as the number of professionals who see the résumé grows exponentially, the fact that the process began as a firsthand referral keeps it personal – unlike if the new grad blindly applied to a job online. Krueger says this method is particularly helpful for finding roles in small companies that have few, unadvertised openings. When companies want to fill those positions, “they're looking at that internal pipeline of people they already know,” he says.

3. Invite the grad to shadow you. “Shadowing is a very classic way of mentoring and helping people,” says Dan Schawbel, career and millennial expert and author of “Promote Yourself: The New Rules for Career Success.” After getting permission from your company, “get this student or recent graduate to come in, and show them firsthand what it’s like to work in an office environment in your profession or industry.”

Schawbel points out that shadowing may help the grad determine what he or she wants – or doesn't want – to do. (Those 9 a.m. conference calls aren't very fun, are they?)

To assure the day goes smoothly for both the shadower and the shadowee, check out these four tipsoutlined by Monster.

4. Help with mock interviews. “We train [students] to read things, know things and take the test,” Krueger says. “You can't read interview questions, know the answer and go to the interview. You actually have to practice.” Here's where you, a list of common interview questions and your phone's video feature come in. And you don't have to be a career expert to be helpful.

“All you're doing is asking them the questions and giving them the opportunity to respond,” he says. “The best part of the mock interview is not necessarily your feedback, but the opportunity to see themselves answering interview questions [and] getting that practice to actually do it.”

5. Be a coach. Again, no expertise necessary. “Sometimes the hardest part of job searching is getting started and making that your full-time job until you get a full-time job,” he says. And you can help keep the grad motivated.

Krueger suggests simply listening to the job seeker's plans and goals for the week – say, reaching out to 30 companies and securing three interviews –and then checking in on how they played out. If applicable, talk about how you can help tweak the strategy. For example, if the job seeker contacted those 30 companies and got no bites, brainstorm more effective ways to communicate with potential employers.

“That's different than Mom and Dad saying, 'Do you have a job yet?,'” Krueger says, because you're holding the grad accountable for her own goals. You're just giving a nudge – which is more useful than a pen.

托福阅读素材之“慢艺术”

Slow art is art created or presented in a way that encourages unhurried viewing and deep contemplation; a work of art that unfolds over a long time.

“慢艺术”是为了鼓励人们从容观看和深思而创造或展示的艺术，是让你花长时间去欣赏的一件艺术品。

Famous art critic Robert Hughes wrote that “We have had a gutful of fast art and fast food. What we need more of is slow art: art that holds time as a vase holds water; art that grows out of modes of perception and whose skill and doggedness make you think and feel; art that isn’t merely sensational, that doesn’t get its message across in 10 seconds, that isn’t falsely iconic, that hooks onto something deep-running in our natures.”

著名艺术评论家罗伯特?休斯曾写道：“我们已经受够了快艺术和快餐。我们更需要的是慢艺术：那些能承载时间的艺术，就像花瓶能承载水一样;那些领会了各种感知方式，灵活又固执地让你去思考和感受的艺术;那些不只带来一时震撼，也不会在10秒内迅速传递信息的艺术，这种艺术不是虚假的偶像文化，而是直抵人性深处的真实。”

A number of museums now offer “slow art” tours or days that encourage visitors to take their time. Rather than check master works off a list as if on a scavenger hunt, you can make a sprawling museum digestible and personal by seeking out only those works that dovetail with your interests.

不少博物馆现在都提供“慢艺术”游览项目或鼓励游客从容观赏的“慢艺术日”。你不必像食腐动物狩猎一般把大师杰作飞速地一览而尽，而是可以找出那些对你口味的作品，然后慢慢地去消化吸收，让你的博物馆之旅变得个性化

篇3：托福听力备考要不要补充背景知识

虽然ETS表示，并不需要考生具备学科背景知识，所有解题信息都会在原文中给出。但事实上，如果学生能够对相应的学科或场景有所了解，可以帮助理解。甚至没全听懂，也可以帮助降低试题难度。

而背景知识包括conversation中的场景词汇知识，和lecture学科基础词汇知识。

备考托福听力的时候需要准备两类词汇，一类是基础词汇，一类是学科词汇。学科词汇又分为学科基础词汇和学科专业词汇。学科基础词汇是可以用单词去解释学科知识，属于必备的工具单词。学科专业词汇则比较抽象，并不需要着重学习，材料中往往会自带解释或替换。

不用基础学生补充听力背景知识有差异

1. 先补充后讲文章

适合基础阶段考生，以提高词汇量为主。但这个阶段题目不是重点，不是为了正确率。

2. 先讲文章后补充

适合强化阶段考生，以讲解题目为主，补充单词和知识为辅。

而“先讲文章后补充”这种类型的补充方式又分为两种：

1、精讲文章同时补充：调动学习兴趣，辅助理解文章;

2、讲完文章和题目之后补充：扩展学科背景，适合能力程度较好的考生。

总而言之，托福听力备考适当学习了解一些学术话题的基础概念背景知识还是很有价值的，希望大家能够做好背景知识的补充，以应对托福听力中的各类专业学术话题。

托福听力中如何挽救你做题的正确率?

托福听力是托福四项科目中比较难以提高的一项，首先是因为对词汇的要求较高，考生不仅需要背会基础词汇和学科基础词汇，还要能在文章中听到单词后瞬间反应出含义，理解上下文意思，但大部分考生平时背单词的习惯和这种对单词读音的快速反应能力要求是不相符的，因为大家都习惯看单词，而不是听单词。其次，单词掌握了以后，还要具备理解句子的能力，在托福听力正常语速下要提取出句子的主干信息，或者通过上下文推知句子的信息。最后，还要具备对段落和篇章信息梳理的能力，要对考点信息有预判和定位，熟悉托福听力的出题点。

如果以上三项基础能力都很扎实，那么恭喜，你已经具备了托福听力通关的基础实力，但这只是拿到理想分数的第一步，更重要的是如何把题目做对，这才是我们接下来要讨论的重点。

很多考生会想，我把材料听懂了，做对题不是水到渠成的事情吗?不完全对，且不说听到、听懂、听准材料信息这三个状态在做题的时候是完全不同的体验，即便听准信息了，也会受到干扰选项的影响，ETS在设计托福听力正确选项和干扰选项时有一套科学严谨的方法，不能因为是形式简单的选择题而掉以轻心。

最近遇到一个学员案例来和大家分享，学员的词汇和语法能力已经足够理解材料，而且基本能够复述出主要信息，所以理解材料基本是没有问题的，但是做题的正确率较低，通过让学员讲述自己选择答案的过程，发现学员做题时有些思路方面的错误，比如学员看到题目时会自己先设想一个“标准”答案，然后用四个选项去匹配自己设想出来的答案，一旦发现匹配不上，就会“将就”着选择自己听到的单词，很容易跳入干扰选项的陷阱，因为听力材料中经常会拿原文出现过的单词做干扰选项。又比如，托福听力中有一个固定题目叫主旨题，学员在选主旨题的答案时，会倾向于选择含有自己印象中比较突出的词或表述的那个选项，没有完整理解选项整体的含义，而一个正确的主旨题答案，必须是一个能包含文章各个部分内容的选项，即概括任何一个部分都适用，而且选定主旨题的答案后，最好双向检验，如果自己选择的是正确答案，那么按照该选项文章结构和逻辑应该是怎样的，是否与自己听到的材料相符。

听力考试其实是对语言综合能力的考察，这里的综合是指在听力的过程中我们需要调动的大脑资源，不简简单单是“听”，更多的是“力”，理解力，想象力，记忆力，推理能力，以及分析题目和选项的能力，等等。有些考生看似能轻松把答案选对，实际上是这些综合实力在他身上发挥作用的体现，而有些考生觉得自己长期陷入难以提分的瓶颈，其实可能在某一环节存在短板，只有找准问题的关键，针对问题制定解决方案，才能挽救自己做题的正确率，才能离好分数越来越近。

托福听力地质学中的“岩石”词汇分类

岩石(rock)一般分为三大类：

(一)火成岩(igneous rock)是指岩浆冷却后(地壳里喷出的岩浆，或者被融化的现存岩石)，成形的一种岩石。

常见的火成岩有：

花岗岩 granite: a very hard grey rock, often used in building

玄武岩 basalt: a type of black rock produced by volcanoes

黑曜石 obsidian: a type of rock that looks like black glass

浮石 pumice: very light grey rock from a volcano

granite basalt obsidian pumice

托福TPO真题链接：

Dating was used to establish that half of the sandstone in the samples was formed at the same time the granite in the Appalachian Mountains was formed. TPO-1

(二)沉积岩(sedimentary rock)是在地表不太深的地方，将其他岩石的风化产物和一些火山喷发物，经过水流或冰川的搬运、沉积、成岩作用形成的岩石。

常见的沉积岩有：

煤 coal: a combustible black or brownish-black sedimentary rock

砂石 sandstone: a type of soft yellow or red rock

石灰石 limestone: a type of rock that contains calcium

页岩 shale: a smooth soft rock which breaks easily into thin flat pieces

石膏 gypsum: a soft white substance

白云石 dolomite: a kind of sedimentary rock

coal sandstone limestone shale gypsum dolomite

托福TPO真题链接：

It was formed from sandstone that solidified somewhere between 150 and 300 million years ago. TPO-1

Another difference, very important today for distinguishing between older lake beds and newer ones, is the location of the limestone formations. TPO-9

(三)变质岩(metamorphic rock)是指受到地球内部力量(温度、压力、应力的变化、化学成分等)改造而成的新型岩石。固态的岩石在地球内部的压力和温度作用下，发生物质成分的迁移和重结晶，形成新的矿物组合。

常见的变质岩有：

大理石 marble: a type of hard rock that becomes smooth when it is polished

石英石 quartzite: hard metamorphic rock consisting essentially of interlocking quartz crystals

板岩 slate: a dark grey rock that can easily be split into flat thin pieces

片麻岩 gneiss: a laminated rock similar to granite

marble quartzite slate gneiss

托福TPO真题链接：

Then they shipped these plastic casts to workshops all over the empire, where they were replicated in marble or bronze. TPO-18

篇4：托福听力备考是否要补充背景知识

很多同学刚开始练托福听力，会觉得听力中的专业术语很多，而自己没有听懂听力素材就是因为这些专业术语，实际上虽说托福出题机构ETS不要求考生掌握相关专业背景知识，但是带着一些背景知识去听文章会有助于我们更快速的理解文章，比如如果你了解恒星的起源，那么很多天文学的文章都会如履平地。因此，托福听力备考补充背景知识并非强制性的要求，但如果是为了提升熟练度让大家更好地听懂理解素材讲了什么，补充背景知识还是很有必要的。

如何补充托福听力的专业背景知识?

一方面，大家可以通过官方模考真题来掌握相关的背景知识，特别是当你听完一篇文章不是很理解文章内容或者某个专业术语时，可以用维基百科(英文版)查询相关的关键词，比如Pleistocene rewilding，Symbiosis，Mass extinction这类的术语，一点一滴积累，当你了解整个托福阅读的常见话题相关背景常识也就基本上掌握了托福听力的基本常识了。

另一方面，可以通过平时点滴的积累来增加相关背景知识，经常看看各类学术性质的新闻或是原版的纪录片，从中寻找一些托福听力经常考的相关学科来听或看(比如生物学，艺术史，天文学等等)。让复习托福听力成为语言能力和常识提升的一种手段，而不仅是为了考试而考试。

托福听力：如何练习长段子精听

阶段：听抄至少3篇。一句一句地听，把句子完整地写下来。不会拼写的写下大致的拼法就行。一句话多放音不超过三遍，即使没有写下来，也不要再回头去听。

第二阶段：听大意至少五篇。以两至三句句子为一个单位，一个单位一听。然后写下这两、三句话的大意。不需要再像阶段一样写下每个单词。

这个阶段练习的是概括能力。托福长段子的长度决定了它的题目数量，一般来说4~5题配上这点长度(200个词左右)，每2~3句话必出一道题才能出够题目数量。

第三阶段：听全文至少5篇。听好之后总结下文章的key point。然后看自己听到的与问题所涉及到的句子是否一致。一致就说明你听到点子上了。那么其他的话就算有没听懂的也无所谓了。

这个阶段练习你对主旨题的把握，以及对重要句子的敏感度。

说明：

1、这个过程是循序渐进的，而且每个阶段的重点不同。所以不要跳掉任何一个阶段或者颠倒阶段次序。

2、每个阶段5篇是个基数，大家觉得不够可以酌情增加。

3、合理安排、认真练习的话，两周就可以把段子题的错误控制在两个左右。

在托福备考的过程中，托福听力的备考理解一些长段子的内容往往被一些英语基础较为薄弱的学生所重视。而然，在这其中，我们又要找到重点的一些环节。

托福听力：怎样提高做题效率

在托福听力考试中，什么样的信息有价值?这是广大考生想在托福听力备考中想要弄懂的问题，判断信息的价值，可以节省我们的时间，提高做题效率。

从conversation题目来看，问题不重要，答案更加重要;答案的开始部分比较重要，因为这里是观点出现的问题，其后对于观点的解释相对次要;不是每一个question + answer的回合都重要，有明确的如Wh—的问题的回合才有价值，其后的起到confirmation作用的内容并不重要;不是每一个观点都重要，确定的观点才应该引起我们的注意，所谓的sometimes， maybe 等词语相关的句子往往只是起到对主要观点的铺垫作用;

相比较来说，lecture 这种题目的出题点更加难以寻找。Conversation的话题内容毕竟都是campus talks，所以难度不会太大;即使偶尔有一两个问题比较难，考生也可以果断地选择放弃，将精力投入到下一个问题中去，所以基本不存在考生在对话题目中根本听不懂或者因为一处听不懂影响对全篇对话理解的情况。

然而，lecture的内容包罗万象，新托福的官方指南给出了46个学科，而实际考试中也可能出现更多的学科和话题;lecture也没有 conversation题目中相对明确的回合概念，很多时候我们不得不根据上下文进行推理，在托福听力考试过程中理顺 lecture 的主要内容。

篇5：托福阅读高频易错话题背景知识补充

托福阅读高频易错话题背景知识补充中世纪农业改革那些事儿

近期托福阅读农业话题出现情况介绍

农业向来是ETS特别喜欢考的一个话题，从农业起源，到具体某个国家或者文明农业发展的状况，从玛雅印加农业到巴厘岛埃及农业，农业的话题充斥着工业革命之前历史时期的各个阶段。纵观最近几场考试：

The Plow and the Horse in Medieval Europe .9.7;

The Medieval Agricultural Revolution 2019.8.25;

New Sources of Power for Agriculture 2019.7.6;

中世纪的农业改革这个话题热度久高不下，接下来小编就跟大家详细聊聊中世纪农业改革那些事。

中世纪工业改革话题背景知识科普分享

中世纪的农业改革重点体现在3个方面：三田制(three-field system)，重型犁(heavy plow)和马在畜力上的使用(plow horse)。

1. three-field system(三田制)

在中世纪之前的罗马时代是二田制，所有的田地一份为二，一半种植(cultivation)，一半休耕(fallow)，但随着时代的发展，人口越来越多，导致食物供不应求，所以这个时期的人们开始使用三田制，将土地一分为三，其中的三分之二用于种植，另外三分之一进行休耕，一方面能够确保粮食的供应，另一方面也保证土地有时机恢复肥沃度。

具体内容如下：

For much of the early Middle Ages, peasants continued the Roman practice of dividing their fields in two leaving one fallow, or uncultivated, for a year, and planting their crops in the other half. Fallow land restored its nutrients, but the practice meant that half the land produced nothing every year. In southern Europe with its drier climate this system of two-field crop rotation continued, but in northern Europe, peasants improved on this system by dividing their land into three parts. One they left fallow, another they planted in the spring, and the third they planted with winter crops. This three-field crop rotation, dependent on more rainfall than southern Europe received, meant that two-thirds instead of one-half of a peasant's land was under production in one year.

2. heavy plow(重型犁)

这个时期的人们把罗马时代的犁(scratch plow)进行了改造，使它更锋利，能够穿透北欧沉重潮湿的泥土，给土地充气，并且将底层的矿物质翻倒地表，有助于庄稼生长，另一方面，重型犁留下犁纹(furrow)，有利于疏通泥土排水，减少洪涝。但新犁很重，需要八匹马/八头牛去拉，个体农民无法负担如此多牲畜，促使农民合作结成马队或者牛队，且为了减少犁地时拐弯，将农田变成长条形(long strips)。

具体内容如下：

A major development in farming was the heavy plow that could cut through the deep, wet, and heavy soils of Northern Europe much better than the light scratch plow. It had three basic parts: the coulter or heavy knife that cut through the soil vertically, the plowshare that cut through the soil horizontally, and the mouldboard, which turned the soil to one side.

There were two advantages to this kind of plow. First, it cut the soil so violently that there was no need for cross plowing as there was with the scratch plow. This saved time, which could be used for, among other things, clearing more land and producing more food. Second, the heavy plow created furrows, little ridges and valleys in each plowed row. In times of drought, water would drain into the valleys and ensure some crops would survive. In times of heavy rains, the crops on top of the ridges would not get flooded out. As a result, peasants could usually look forward to at least some crops to harvest even in bad years. The furrows the heavy plow created also meant that the rich alluvial bottomlands by rivers could be farmed without their frequent floods doing too much damage. The heavy plow also fed into the feedback cycle of more food, population growth, etc.

3. plow horse(马的使用)

马的使用也是这个时期的重点突破，之前不用马是因为套在牛脖子上的collar不适合马，后来人们对这个collar进行改造，研制出了新型马具，使得马可以在耕地上发挥作用。马的工作时间更长，效率更高，促进了农业产出(yield)，且马可以用来运输粮食去更远的地方，推动区域经济的发展。

相应文章如下：

Oxen are slow and unintelligent compared to horses, but peasants could not use horses to pull plows until they devised a different kind of harnessing than the strap that circled an ox's neck. With a harness resting on its shoulders instead of its neck, a horse could be used to plow, and horses could walk more quickly and work longer hours than oxen. They also required less guidance, since they understood verbal signals to turn or to stop. Heavier, wheeled plows pulled by suitably harnessed horses meant that peasants could work more land in a day than ever before. Whether an increase in population across western Europe, but particularly in the north, stimulated innovations or whether such innovations contributed to a rise in population, the cumulative effect of these changes in agriculture was apparent in the tenth century. Conditions in Europe were ripe for an economic and cultural upswing.

这三大改革，大大促进了农业的发展，也使得中世纪进入了它发展的繁盛期，历史上称之为The High Middle Ages。

中世纪农业改革的相关背景知识就介绍到这里，小编希望各位考生能够认真阅读有所收获，并运用到后期的备考甚至是实战的阶段当中。

托福(TOEFL)考试阅读模拟试题

Question 31-40

If the salinity of ocean waters is analyzed, it is found to vary only slightly from place to place. Nevertheless, some of these small changes are important. There are three basic processes that cause a change in oceanic salinity. One of these is the subtraction of water from the ocean by means of evaporation —— conversion of liquid water to water vapor. In this manner, the salinity is increased, since the salts stay behind. If this is carried to the extreme, of course, white crystals of salt would be left behind.

The opposite of evaporation is precipitation, such as rain, by which water is added to the ocean. Here the ocean is being diluted so that the salinity is decreased. This may occur in areas of high rainfall or in coastal regions where rivers flow into the ocean. Thus salinity may be increased by the subtraction of water by evaporation, or decreased by the addition of fresh water by precipitation or runoff.

Normally, in tropical regions where the sun is very strong, the ocean salinity is somewhat higher than it is in other parts of the world where there is not as much evaporation. Similarly, in coastal regions where rivers dilute the sea, salinity is somewhat lower than in other oceanic areas.

A third process by which salinity may be altered is associated with the formation and melting of sea ice. When seawater is frozen, the dissolved materials are left behind. In this manner, seawater directly beneath freshly formed sea ice has a higher salinity than it did before the ice appeared. Of course, when this ice melts, it will tend to decrease the salinity of the surrounding water.

In the Weddell Sea, off Antarctica, the densest water in the oceans is formed as a result of this freezing process, which increases the salinity of cold water. This heavy water sinks and is found in the deeper portions of the oceans of the world.

3l. What does the passage mainly discuss?

(A) The elements of salt

(B) The bodies of water of the world

(D) The salinity of ocean water

32. The word “this” in line 5 refers to

(A) ocean

(B) evaporation

(D) crystals

33. According to the passage, the ocean generally has more salt in

(A) coastal areas

(B) tropical areas

(D) turbulent areas

34. All of the following are processes that decrease salinity EXCEPT

(A) evaporation

(B) precipitation

(D) melting

35. Which of the following statements about the salinity of a body water can best be

inferred from the passage?

(A) The temperature of the water is the most important factor.

(B) The speed with which water moves is directly related to the amount of salt.

(D) Various factors combine to cause variations in the salt content of water.

36. The word “altered” in line 16 is closest in meaning to

(A) determined

(B) changed

(D) needed

37. The world “it” in line 18 refers to

(A) sea ice

(B) salinity

(D) manner

38. Why does the author mention the Weddell Sea?

(A) To show that this body of water has salinity variations

(B) To compare Antarctic waters with Arctic waters

(D) To point out the location of deep waters

39. Which of the following is NOT a result of the formation of ocean ice?

(A) The salt remains in the water.

(B) The surrounding water sinks.

(D) The water becomes denser.

40. What can be inferred about the water near the bottom of oceans?

(A) It is relatively warm.

(B) Its salinity is relatively high.

(D) It evaporates quickly.

托福(TOEFL)考试阅读模拟试题

Questions 21-30

Glacier National park in Montana shares boundaries with Canada, an American Indian reservation, and a national forest. Along the North Fork of the Flathead River, the park also borders about 17,000 acres of private lands that are currently used for ranching, timber, and agriculture. This land is an important part of the habitat and migratory routes for several endangered species that frequent the park. These private lands are essentially the only ones available for development in the region.

With encouragement from the park, local landowners initiated a land-use planning effort to guide the future of the North Fork. The park is a partner in an interlocal agreement that calls for resource-managing agencies to work together and with the more than 400 private owners in the area. A draft plan has been prepared, with the objective of maintaining traditional economic uses but limiting new development that would damage park resources. Voluntary action by landowners, in cooperation with the park and the county, is helping to restrict small-lot subdivisions, maintain wildlife corridors, and minimize any harmful impact on the environment.

The willingness of local landowners to participate in this protection effort may have been stimulated by concerns that Congress would impose a legislative solution.

Nevertheless, many local residents want to retain the existing character of the area.

Meetings between park officials and landowners have led to a dramatically improved understanding of all concerns.

21. The passage mainly discusses

(A) the endangered species in Glacier National Park

(B) the protection of lands surrounding Glacier National Park

(D) conservation laws imposed by Congress

22. Why are the private lands surrounding Glacier National Park so important?

(A) They function as a hunting preserve.

(B) They are restricted to government use.

(D) They contain natural habitats of threatened species.

23. The word “ones” in line 6 refers to

(A) private lands

(B) endangered species

(D) ranching, timber, agriculture

24. The word “initiated” in line 7 is closest in meaning to

(A) started

(B) requested

(D) considered

25. The relationship between park officials and neighboring landowners may best be

described as

(A) indifferent

(B) intimate

(D) disappointing

26. It can be inferred from the passage that a major interest of the officials of Glacier

National Park is to

(A) limit land development around the park

(B) establish a new Park in Montana

(D) settle border disputes with Canada

27. In lines 15-16, the author implies that landowners might be responding to environmental

concerns for which of the following reasons?

(A) They wish to stimulate economic growth.

(B) They wish to improve their public image.

(D) They fear federal legislation.

28. The word “stimulated” in line 16 is closest in meaning to

(A) motivated

(B) anticipated

(D) undermined

29. The word “retain” in line 17 is closest in meaning to

(A) preserve

(B) possess

(D) improve

30. Where in the passage does the author mention the purpose of the plan developed

by local landowners and park officials?

(A) Lines 1-2

(B) Lines 4-6

(D) Lines 15-17

篇6：托福阅读背景知识

托福阅读背景知识知多少阅读背景知识汇总

一.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 )

化石构成。化石比原物更沉重(矿物质环境)

化石形成原因。坚硬物质，迅速掩埋。

化石与动物的进化关系。

3.人的左右手

使用工具。证据：敲击的划痕;手柄的形状。

牙齿上的划痕。

大脑左右半球的大小差别;趾骨的粗细差别。

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。

二.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。

三.动植物题材(必考)

1.植物学题材(不多见)

地衣、苔、真菌、蘑菇最常见。

树冠上方生物。

植物在生态平衡中的作用。

2.动物学题材(90%以上)

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)。

考动物进化(evolution)。

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

动物的生活习性最为多见。

群居(social animal)动物的习性

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。

蜜蜂：群居个性;“8”字舞;蜜蜂智能;防御;天敌—大黄蜂。

大猩猩：智能：猩际关系

迁徙(migration )

野鸭、大雁：日照长短;辨别方向。

伪装(camouflage)、花拟态(mimicry )

四.美国历史题材

1.美国发展线索

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)

英国定居阶段(English settlement )

1607第一个定居点Captain John Smith影响清教徒

1620五月花号

殖民时期(colonial era )

独立战争(American Revolution )

新的国家(new nation)：南北不均衡

南北战争(Civil War )

战后重建。持续近1。

西进运动(Westward movement )

工业化大增长

world war I &; II

2.“大熔炉”：地理位置;民族融合1960’s;文化融合。

3.邮政。小马快递;铁路邮政。

五.地理学题材

1.地理现象、土壤构成、降雪降雨。

2.冰川(glacier)、形成(foundation) à移动冰川(surge glacier )à危险

3.地球构成：地心构成

4.板块构成学说

托福阅读真题原题+题目

Tulips are Old World, rather than New World, plants, with the origins of the species lying in Central Asia. They became an integral part of the gardens of the Ottoman Empire from the sixteenth century onward, and, soon after, part of European life as well. Holland, in particular, became famous for its cultivation of the flower.

A tenuous line marked the advance of the tulip to the New World, where it was unknown in the wild. The first Dutch colonies in North America had been established in New Netherlands by the Dutch West India Company in 1624, and one individual who settled in New Amsterdam (today's Manhattan section of New York City) in 1642 described the flowers that bravely colonized the settlers' gardens. They were the same flowers seen in Dutch still-life paintings of the time: crown imperials, roses, carnations, and of course tulips. They flourished in Pennsylvania too, where in 1698 William Penn received a report of John Tateham's Great and Stately Palace, its garden full of tulips. By 1760, Boston newspapers were advertising 50 different kinds of mixed tulip roots. But the length of the journey between Europe and North America created many difficulties. Thomas Hancock, an English settler, wrote thanking his plant supplier for a gift of some tulip bulbs from England, but his letter the following year grumbled that they were all dead.

Tulips arrived in Holland, Michigan, with a later wave of early nineteenth-century Dutch immigrants who quickly colonized the plains of Michigan. Together with many other Dutch settlements, such as the one at Pella, Iowa, they established a regular demand for European plants. The demand was bravely met by a new kind of tulip entrepreneur, the traveling salesperson. One Dutchman, Hendrick van der Schoot, spent six months in 1849 traveling through the United States taking orders for tulip bulbs. While tulip bulbs were traveling from Europe to the United States to satisfy the nostalgic longings of homesick English and Dutch settlers, North American plants were traveling in the opposite direction. In England, the enthusiasm for American plants was one reason why tulips dropped out of fashion in the gardens of the rich and famous.

1. Which of the following questions does the passage mainly answer?

(A) What is the difference between an Old World and a New World plant?

(B) Why are tulips grown in many different parts of the world?

(D) Where were the first Dutch colonies in North America located?

2. The word integral in line 2 is closest in meaning to

(A) interesting

(B) fundamental

(D) overlooked

3. The passage mentions that tulips were first found in which of the following regions?

(A) Central Asia

(B) Western Europe

(D) North America

4. The word flourished in line 11 is closest in meaning to

(A) were discovered

(B) were marketed

(D) thrived

5. The author mentions tulip growing in New Netherlands, Pennsylvania. and Michigan in order to

illustrate how

(A) imported tulips were considered more valuable than locally grown tulips

(B) tulips were commonly passed as gifts from one family to another

(D) attitudes toward tulips varied from one location to another

6. The word grumbled in line 16 is closest in meaning to

(A) denied

(B) warned

(D) explained

7. The passage mentions that one reason English and Dutch settlers planted tulips in their

gardens was that tulips

(A) were easy to grow

(B) had become readily available

(D) reminded them of home

8. The word they in line 20 refers to

(A) tulips

(B) plains

(D) plants

9. According to the passage , which of the following changes occurred in English gardens during

the European settlement of North America?

(A) They grew in size in order to provide enough plants to export to the New World.

(B) They contained a wider variety of tulips than ever before.

(D) They decreased in size on the estates of wealthy people.

10. The passage mentions which of the following as a problem associated with the importation of

tulips into North America?

(A) They were no longer fashionable by the time they arrived.

(B) They often failed to survive the journey.

(D) Settlers knew little about how to cultivate them.

PASSAGE 85 CBADC CDCCB

篇7：托福听力背景知识精选

植物学(botany)是生物学的分支学科。主要研究植物的结构(structure)、生长(growth)、繁殖(reproduction)、新陈代谢(metabolism)、发展(development)、化学特征(chemical properties)、疾病(disease)及进化(evolution)等等。研究可以从多个角度切入，通过研究植物的细胞器(organelle)、细胞(cell)、组织(tissue)、器官(organ)、个体(individual)、种群(population)，可以了解到其分子(molecular)、基因(genetic)和生物化学(biochemistry)各方面的信息。人类早期对于植物的研究主要出于辨别植物能否食用，能否入药及是否有毒，这也使植物学成为最老的一门学科之一。当今植物学家研究了超过550000种植物，目的在于开发、利用、改造和保护植物资源，让植物为人类提供更多的食物、纤维、药物、建筑材料等。

植物的基本结构

和其他话题一样，考生对于植物学的了解并不需要多么专业，但提醒各位考生，至少要了解一些和植物相关的基本词汇才能理解文章所要表达的内容。以一棵树为例，其组成部分主要包括了树干(trunk)、树皮(bark)、根(root)、树枝(branch/bough)、细枝(twig)、嫩芽，幼苗(shoot)、树叶(leaves)、叶柄(stalk)等。植物的花(flower)包括了花苞(bud)、花瓣(petal)、花蜜(nectar)、花粉(pollen)、雌蕊(pistil)、雄蕊(stamen)等。植物的果实(fruit)包括了果皮(peel)、果肉(flesh)、种子(seed)等，有的种子外部会包裹坚硬的壳(shell)，以保护种子不受伤害。

植物的光和作用(photosynthesis)

不论对于植物还是人类乃至整个地球来说，光和作用都是非常重要的过程。简单来说，光和作用就是绿色植物利用光能将其所吸收的二氧化碳(carbon dioxide)和水转化为有机物(organics)，并释放出氧气(oxygen)的过程。存在于叶子中的叶绿素(chlorophyll)和一些酶(enzyme)在光合作用中起到了举足轻重的作用。在这个过程中，植物为人类消耗了我们生产、生活中所排放的二氧化碳气体，也就是通常意义上的温室气体(greenhouse gas)。植物释放的氧气是人类生存必不可少的。同时，植物生产储存的有机物又为动物提供能量来源，因此植物被称为食物链(food chain)的生产者。

植物的用途

除了作为果腹的食物，植物有许多其他的重要用途。许多药物成分的提取主要是来自于植物，比如阿司匹林(asprin)的成分就源自于柳树皮(bark of willow trees);像吗啡(morphine)这类麻醉止痛剂(narcotic analgesics)则是从罂粟(opium poppy)中提取的。我们常常用来提神的咖啡(coffee)、巧克力(chocolate)、烟草(tobacco)和茶(tea)也是从植物中得来的。通过发酵(ferment)如大麦(barley)、米(rice)和葡萄(grape)这些植物，我们还能得到不同口味的美酒。

生活中，植物能为我们提供棉(cotton)、麻(hemp)等织物(fabrics)，丝绸(silk)的生产也离不开桑树(mulberry tree)的存在。有的植物还能做成绳锁(rope)，制作橡胶(rubber)，为人类生活带来便利。

作为一种方便易得的有机体，植物可以用来做各种研究基本生命过程(life process)的实验，比如细胞的分裂(cell division)，蛋白质的合成(protein synthesis)等。而这些研究并不需要背负动物实验或人体实验的伦理包袱。奥地利的门德尔(Gregor Mendel)通过研究豌豆形状而得出了遗传的基本原理(genetic laws of inheritance)。

考题体现

在各种托福考试的参考书中都出现过关于植物学的考题，如TPO中有一篇讲nightcap oak的文章，从整体上介绍了这种特殊植物的生长繁殖特点。比较有特色的是Delta中出现了介绍两种植物的生长激素(hormone)：乙烯(ethylene)和植物生长素(auxin)。话题的切入点很小，中心名词也非常陌生，但只要能根据所描述解释的内容和实例，不难理解文章所要表达的主旨，考生甚至能把实际生活与之联系。

经典加试题中也有一篇有关大王花(Corpse Flower/Rafflesia)的介绍。教授一开始介绍植物分类(classification)，提到分类中的种(species)，属(genus)，目(order)，她说植物的分类很难，一些特性比较特殊的植物特别是这个样子。她提出植物的分类不能完全依靠其花的形态和特性。教授举例讲到大王花，开花时会散发腐臭的味道，以吸引蝇类传播花粉。她举了印度尼西亚(Indonesia)的一种植物M，它的花很特别，很大(图片显示它的直径有一个手臂这么长，颜色为绛红)，有难闻的味道，像肉，但是最后发现它们不是一个目的。大王花生长在很恶劣的环境中，其它的植物都不能生长。这种植物虽然有食物的来源，但是它还是会抓昆虫(insect)吃，因为它不能从土壤中得到足够的营养，所以要通过这种方式来获取所需的营养。然后教授说了它是如何抓虫的。经过很长时间的研究，专家发现它和紫罗兰 (violet)、柳树 (willow) 等是属于一个目的，后提到幼时的紫罗兰，也会散发那种味道。又提到另一种南美洲的植物和它是同一目的，但是花很小，味道也不难闻。学生提问不能测DNA吗，教授说这种大花基本不进行光合作用，没法提取一般植物能提取到的DNA。在DNA分析技术成熟之前根本无法将他们并为同类，由于他们的特征差异太大。教授还提到这种植物的交配不易，其一气味难闻致使传蜜的动物不易接近，其二它每年只开一次花，且花分雌雄。所以要这么多先天条件凑齐不易，所以很少有人有机会看到开花的全过程。后来又讲了这种花很有可能灭绝，原因是要苍蝇帮忙运花粉，要同种的花在一起，等等。要这些条件同时发生，是小概率事件。

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