对比：作者站在哪一边

上一章的因果是一条箭头，这一章的对比是一道分界线。But、although、not…but、used to…now，这些词把一段话切成两半，一半是作者不同意的、让步的、过去的，另一半是他真正想说的。

题目的答案只会落在其中一边，而出题人的陷阱往往就放在另一边，用的还是原文的词。

在讲具体的逻辑词之前，先说一个英文写作的习惯。知道了这个习惯，你会明白为什么考研文章里 but 这么多，为什么作者明明在批评，读起来却像在夸。

先说好话再说 but：英语里的三明治

美国人要反对一件事、批评一个人的时候，很少开口就说“不行”。常见的说法是三层：先肯定，再用 but 或 however 说出真正的意见，最后再肯定一句收尾。职场培训里管这个叫三明治表达法，两片面包是客气话，中间夹的才是馅。

下面几个例子都是真实的原话，不是为了这本书编的。

网上吵架也是这样吵的

2007 年，Dropbox 的创始人在程序员论坛 Hacker News 上发帖介绍自己的产品。有一位用户（网名 BrandonM）留言提了三点疑问，其中一点是：说它能替代 U 盘，不太站得住。创始人逐条解释以后，BrandonM 又回了一段：

You are correct that this presents a very good, easy-to-install piece of functionality for Windows users. The Windows shortcomings that you point out are certainly problems, and I think that your software does a good job of overcoming that.
Your use-case described in #2 does make sense, but I still agree with others' comments here that claiming that it replaces USB drives is a bad idea in general.
All of your feedback was well-thought-out and appreciated; I only hope that I was able to give you a sneak preview of some of the potential criticisms you may receive. Best of luck to you!

第一段面包很厚：你说得对、做得好。第三段面包也很厚：你的回复很用心，祝你好运。可他的立场一个字没改，全在 but 后面：说它能替代 U 盘，我还是觉得不对。只读第一句的人，会以为他被说服了。

顺带一提，这位用户当初对 Dropbox 的质疑，后来常被当作互联网上最有名的“看走眼”之一，因为 Dropbox 后来成了上市公司。但单看这段回复的语言，它是一个教科书式的三明治。

2025 年 2 月，AI 研究者 Andrej Karpathy 在 X 上发了一条帖子，造了 vibe coding 这个词，形容写程序时完全交给 AI、自己不看代码。帖子的最后一句是：

I'm building a project or webapp, but it's not really coding - I just see stuff, say stuff, run stuff, and copy paste stuff, and it mostly works.

but 前面是表面上看起来的样子（我在做项目、做网站），but 后面是他真正要说的判断（这其实不算写代码）。这个词后来流行开来，但它最初的定义就在这个 but 后面：不算写代码。

正式的文章也是这样写的

1963 年，马丁·路德·金在伯明翰的监狱里写了一封公开信，回应八位白人牧师对他的批评。开头先给对方戴了一顶高帽：

But since I feel that you are men of genuine good will and that your criticisms are sincerely set forth, I want to try to answer your statement in what I hope will be patient and reasonable terms.

（我相信你们是真心善意的人，批评也是诚恳的。）然后才开始反驳。信里最有名的一处反驳，用的是先让步、再 but：

You deplore the demonstrations taking place in Birmingham. But your statement, I am sorry to say, fails to express a similar concern for the conditions that brought about the demonstrations.

It is unfortunate that demonstrations are taking place in Birmingham, but it is even more unfortunate that the city's white power structure left the Negro community with no alternative.

两句话的前半句都在承认对方说的有道理：游行确实令人遗憾。后半句才是他的观点：更该遗憾的是逼出游行的那些条件。I am sorry to say（很遗憾我得说）这种插入语，本身也是一片薄薄的面包。

论文里也是这样写的

学者批评同行时要格外客气，所以论文把这个习惯用得更讲究。

2017 年，八位研究者（多数来自 Google）发表了 Attention Is All You Need，提出了 Transformer，今天的 ChatGPT、Claude、DeepSeek 都建立在它上面。它的引言是标准的文献综述写法：

Recent work has achieved significant improvements in computational efficiency through factorization tricks and conditional computation, while also improving model performance in case of the latter. The fundamental constraint of sequential computation, however, remains.

Attention mechanisms have become an integral part of compelling sequence modeling and transduction models in various tasks… In all but a few cases, however, such attention mechanisms are used in conjunction with a recurrent network.

In this work we propose the Transformer…

每一段都是先肯定前人（取得了显著进步、已经成为不可或缺的一部分），however 之后指出没解决的问题。紧接着下一段就是“本文提出……”。论文里的面包后面跟的往往不是第二片面包，而是这篇论文本身：however 后面的空白，就是作者要填的东西。

再早一点，1953 年 Watson 和 Crick 在《自然》上发表 DNA 双螺旋结构的论文，第二段就要否定当时最有名的化学家鲍林的模型：

A structure for nucleic acid has already been proposed by Pauling and Corey. They kindly made their manuscript available to us in advance of publication. … In our opinion, this structure is unsatisfactory for two reasons: …

这里连 but 都没有，可结构一样：先说对方好心地提前把手稿给了我们看，再说我们认为这个结构有两处不对。客气话后面跟的是一场学术竞赛的胜负。

所以读英文评论和论文有一个窍门：看到一连串好话，先别急着下结论，往后找 but 和 however。作者在它们后面说的，才是他的立场，也往往是这篇文章存在的理由。

考研文章就是从这种文章里选的

考研阅读的文章来自英美报刊的评论，作者写作的习惯和论文作者一样。2018 英语一 Text 3 整篇文章就是一个三明治：

• 第一句先给双方说好话：any fair-minded assessment … must start by acknowledging that both sides mean well（双方的出发点都是好的）。
• 接着肯定 AI 用于医疗潜力巨大，马上 but：它可能让权力进一步集中到科技巨头手里。后面三段全是批评，批评隐私法没抓住要害，担心数据被私人垄断。
• 最后一句又回到肯定：Ms Denham's report is a welcome start（监管者的报告是个好的开始）。

这篇文章的五道题，考的几乎全是中间那层馅：

原文This practice does not address the real worry. It is not enough to say that the algorithms DeepMind develops will benefit patients and save lives. What matters is that they will belong to a private monopoly which developed them using public resources.

According to the last paragraph, the real worry arising from this deal is ____

• Athe vicious rivalry among big pharmas.
• Bthe ineffective enforcement of privacy law.
• Cthe uncontrolled use of new software.
• Dthe monopoly of big data by tech giants.

题目问最后一段说的“真正的担忧”。答案是 D，科技巨头对大数据的垄断，正是夹在两层好话中间的那句 What matters is that they will belong to a private monopoly。

放到解题上

认出三明治以后，做题有三条规矩：

1. 答案多在馅里。 题干问作者的观点、担忧、问题、建议，去 but、however 后面找。
2. 面包常被做成干扰项。 开头和结尾的好话是原文写着的，出题人很喜欢把它们放进选项，等只读了第一句或最后一句的人来选。这篇文章第 35 题的 appreciative（赞赏）就是一片面包。
3. 结尾的好话决定程度，不决定方向。 三明治的作者是在批评，但没有全盘否定，所以他的态度通常是有保留的（cautious、doubtful），不会是轻蔑（contemptuous），也不会是赞赏（appreciative）。这一条在后面态度题那一节还会用到。

把三明治的两片面包拿掉，中间那个 but 单独拿出来，就是下面要讲的转折。

转折：题干带负面词，答案在 But 之后

这是最常见的一种。题干里出现 problem、concern、risk、challenge、drawback 这类负面词，原文往往是先说好处，再用 But 转出问题，答案就在 But 后面。

原文But these open-source programs are built by scraping images from the internet, often without permission and proper attribution to artists.

The problem with open-source AI art generators is that they ____

• Alack flexibility in responding to prompts.
• Bproduce artworks in unpredictable styles.
• Cmake unauthorized use of online images.
• Dcollect user information without consent.

题干 The problem with open-source AI art generators，原文前两句一直在说这类工具多厉害，输入一段文字就能生成接近名家风格的图。第三句 But these open-source programs are built by scraping images from the internet, often without permission，转折之后才是问题。A、B 两个选项拿的是转折前面的内容，还说反了。

反过来，题干问“人们原本以为”“通常认为”“过去的做法”，答案在转折之前。

让步：被让步的那半句是陷阱

让步比转折更隐蔽。作者先承认一点（although、while、may…but、of course、admittedly），然后收回来说自己的观点。被承认的那一点是真的，但不是重点，出题人特别喜欢把它做成选项。

原文According to Sichel, although the falling price of nails was driven partly by cheaper iron and cheaper energy, most of the credit goes to nail manufacturers who simply found more efficient ways to turn steel into nails.

What played the major role in lowering the price of nails after the late 1700s?

• AIncreased productivity.
• BWider use of new energies.
• CFiercer market competition.
• DReduced cost of raw materials.

D · 答非所问　原料变便宜（cheaper iron）确有其事，但在 although 让步从句里只是 partly，不是题干问的 major role。

题目问钉子价格下降的主要原因。原文说：although 降价 partly 是因为铁和能源变便宜了，most of the credit goes to 制造商找到了更高效的造钉方法。

D 的“原材料变便宜”是原文明明白白写着的，可它在 although 后面，还带着 partly。题干的 major role 和原文的 most of the credit 对得上，主因在主句里。这类题如果只看“原文有没有提到”，D 一定会选；看清了让步结构，就知道它只是次要原因。

纠正：not X but Y，Y 才是观点

not X but Y、rather than、instead of、on the contrary，这几个词的意思都是：别人以为是 X，其实是 Y。作者的观点是 Y，X 是用来垫背的。

真题里 rather than 出现了 51 次。比如 2018 英语一第 33 题，原文说数据的价值来自处理和整合，not the mere possession of bits（而不是单纯拥有数据），正确选项说的就是“数据的价值来自处理”。

不过这条规律也要看题干灵活用。比如题目问的是作者质疑、反对什么，答案反而落在 X 那一边。

今昔：问现在，就别拿过去的那一边

used to、once、in the past 和 now、today、no longer 构成另一种对比。题干问今天，就去 now 那一边找；问过去，就去 used to 那一边找。

原文Today’s tip requests are often not connected to the salary and service norms that used to determine when and how people tip. Customers in the past nearly always paid tips after receiving a service, such as at the conclusion of a restaurant meal, after getting a haircut or once a pizza was delivered. That timing could reward high-quality service and give workers an incentive to provide it.

Compared with tips in the past, today’s tips ____

• Aare paid much less frequently.
• Bare less often requested in advance.
• Chave less to do with service quality.
• Dcontribute less to workers’ income.

这道题有意思的地方是三个错误选项都是“正反颠倒”：A 说今天的小费付得更少，原文说顾客被要小费 too often；B 说更少事先索要，原文说事先索要 becoming more common；D 说对工人收入贡献更小，原文说 further supplementing the income。三个都把“今天”这一边的情况说反了，只有 C 和原文一致：今天的小费和服务好坏关系不大了。

态度题：先判正负，再判程度

态度题是对比的特殊形式：作者对一件事要么支持，要么反对，要么支持但有保留。640 道阅读题里只有 28 道态度题，但它几乎有一条铁律：

中性的选项不选。 tolerant、indifferent、ambiguous、objective、uncertain 这类词在态度题的选项里出现了 25 次，是正确答案的只有 1 次。

道理很简单。出题人挑出来出态度题的文章，作者一定有明确的立场；作者写评论就是为了表态，“宽容”“漠不关心”“模棱两可”根本不是一篇评论文章该有的态度。

排除中性词以后，剩下的正面词和负面词，去文章里找作者自己的评价：

1. 先分清是作者的话还是他引用的别人的话。“某专家认为”不等于作者认为。
2. 作者的评价多在最后一段，常常会推翻前面的让步。
3. 再判程度。supportive、appreciative 是肯定；cautious、doubtful 是有保留；critical、skeptical 是否定；contemptuous、sarcastic 是轻蔑，程度太重，很少选。

原文The potential of this work applied to healthcare is very great, but it could also lead to further concentration of power in the tech giants. It is against that background that the information commissioner, Elizabeth Denham, has issued her damning verdict against the Royal Free hospital trust under the NHS, which handed over to DeepMind the records of 1.6 million patients in 2015 on the basis of a vague agreement which took far too little account of the patients’ rights and their expectations of privacy. DeepMind has almost apologized. The NHS trust has mended its ways. Further arrangements — and there may be many — between the NHS and DeepMind will be carefully scrutinised to ensure that all necessary permissions have been asked of patients and all unnecessary data has been cleaned. There are lessons about informed patient consent to learn. But privacy is not the only angle in this case and not even the most important. Ms Denham chose to concentrate the blame on the NHS trust, since under existing law it “controlled” the data and DeepMind merely “processed” it. But this distinction misses the point that it is processing and aggregation, not the mere possession of bits, that gives the data value. The great question is who should benefit from the analysis of all the data that our lives now generate. Privacy law builds on the concept of damage to an individual from identifiable knowledge about them. That misses the way the surveillance economy works. The data of an individual there gains its value only when it is compared with the data of countless millions more. The use of privacy law to curb the tech giants in this instance feels slightly maladapted. This practice does not address the real worry. It is not enough to say that the algorithms DeepMind develops will benefit patients and save lives. What matters is that they will belong to a private monopoly which developed them using public resources. If software promises to save lives on the scale that drugs now can, big data may be expected to behave as a big pharma has done. We are still at the beginning of this revolution and small choices now may turn out to have gigantic consequences later. A long struggle will be needed to avoid a future of digital feudalism.

The author’s attitude toward the application of AI to healthcare is ____

• Aambiguous.
• Bcautious.
• Cappreciative.
• Dcontemptuous.

A · 偷换概念　作者的立场清楚：肯定潜力，但警惕垄断。ambiguous（模棱两可）把“既看到好处又看到风险”误当成态度不明。

还是前面那篇三明治文章。作者先说 AI 用于医疗 The potential … is very great，再用 but 说它可能让权力进一步集中到科技巨头手里，结尾又说监管报告是个好的开始。先肯定、再警惕、最后有保留地肯定，就是 cautious。C 的 appreciative 只吃到了面包，取的是 but 前面那一半；A 的 ambiguous 把“看到好处也看到风险”误读成了“态度不明”，其实作者的立场很明确。

同样的结构小一点也照样出题。2021 英语二第 30 题，原文介绍完“英国粮食自给”的种种好处，紧跟一句 Sounds great — but how feasible is this vision?，后面几段全在算账说明做不到，作者的态度是 doubtful。

怎么练

读每一段的时候，在段尾写一个符号：+ 表示作者在肯定，− 表示否定，→ 表示转向。一篇文章读完，这一串符号就是作者的思路。做题时题干问的是哪一段、哪个对象，看它在 + 还是 − 那一侧，答案的方向就定了，四个选项通常能直接排掉两个。

把下面这张表记熟，它是本站从全部真题里归纳出来的逻辑信号，每一种后面附了一道例题：