1.The irony of the historian's craft is that its practitioners always know that their efforts are but contributions to an unending process.

【参考译文】历史学家这一行的讽刺性就在于实践者清楚地知道他们的努力只不过是对无休止过程的付出而已。

【结构分析】此句的主干结构可拆分如下 ：The irony (of the historian's craft) is that its practitioners always know that their efforts are but contributions (to an unending process).

此句的主语是The irony(后面括号中的of短语是其后置定语），谓语是系动词is， that引导名词性从句作表语（即表语从句）；在表语从句中，谓语动词know后又接that从句， 亦是名词性从句，作动词know的宾语（即宾语从句）；在画线的宾语从句部分，but作“only/ just”解，句末括号中的不定式短语to...是contributions的后置定语;故此句共有两个that引 导的名词从句，分别作表语和宾语（即表语从句和宾语从句）。

【知识链接】irony讽刺性；craft手/.丁艺，行/职业，船，飞行器，例如：〜union同行丁. 会；practitioner (源自 practice)从业者，实践者；but 相当于 only，just 仅仅;contribution to...对……的贡献，此处根据语境的需要调整翻译为“付出”;unending无休止的，没有尽头的 (接近endless) ；process过程，丁艺。例如：in the〜of在......过程中，secret〜s秘方/秘密.丁.艺。

2. What is harder to establish is whether the productivity revolution that businessmen assume they are presiding over is for real.

【参考译文】商界认为他们正主导的生产率革命是否属实是更加难以定论的事情。 

【结构分析】 (What is harder to establish)is (whether the productivity revolution that businessmen assume they are presiding over is for real).

此句的主语是 what 引导的名词性从句（即主语从句），谓语是系动词is，表语是whether引导的名词性从句（即表语从句），故此句中也包含了两个名词性从句；值得关注的是，在whether引导的表语从句中：主语是the productivity revolution，谓语是is，表语是固定搭配for real，両线部分是that引导的一个较复 杂的定语从句，修饰从句的主语revolution。

【知识链接】establish建立，确定，例如〜a family建立一个家庭，〜sb's identity确 定某人的身份；productivity生产率;assume认为，假设；businessmen商人，此处是名词复数 形式表示“一类人，可引申为商界；preside over主持/主导；for real真实的（构成形式类似 于 for free)

3. Galileo's greatest glory was that in 1609 he was the first person to turn the newly invented telescope on the heavens to prove that the planets revolve around the sun rather than around the earth.

【参考译文】伽利略最辉煌的业绩在于他在1609年个把新发明的望远镜对准天空，以证实行星是围绕太阳旋转而不是围绕地球旋转的。

【结构分析】 Galileo's greatest glory was that in 1609 he was the first person (to turn the newly invented telescope on the heavens) (to prove that the planets revolve around the sun rather than around the earth).

句子主干结构是：Galileo's greatest glory 是主语，系动词 was是谓语，that引导表语从句；应关注的是that表语从句里面两个不定式短语的作用：to turn...是the first person的后置定语，而to prove that...则作动词turn的目的状语；在目的状语里，prove后面的that从句（画线部分)是宾语从句；在此宾语从句中，需关注revolve保持原形的用法，它和前面的动词时态不一致，原因在于此从句的内容是一条客观真理。

【知识链接】glory辉煌，光荣；heaven天堂，天空；planet行星；revolve around围绕......旋转；the newly invented telescope 新发明的望远镜；turn...on...把......指向 /转向;rather than 而不是。

4.One difficulty is that almost all of what is called behavioral science continues to trace behavior to states of mind，feelings，traits of character，human nature，and so on.

【参考译文】闲难之一在于:所谓的行为科学几乎全都依然从心态、情感、性格特征、人 性等方面去寻找行为的根源。

【结构分析】 One difficulty is that almost all of what is called behavioral science continues to trace behavior to states of mind，feelings，traits of character> human nature， and so on.

此句主语是One difficulty，谓语是系动词is，表语是that引导的名词性从句（即表语从句）；复杂的是，在that表语从句中：all of what is called behavioral science是该从句中的 主语，谓语部分是continues to trace，宾语是behavior，后面的介词to短语是地点状语。

注：what is called behavioral science 是 what 引导的名词性从句，相当于 the thing (that is called behavioral science)，作前面介词of的宾语（即宾语从句）。

【知识链接】behavioral science行为科学；state of mind心态，意识状态;trait显著的特征/特点；human nature人性；trace追踪，追寻，探究。

例如：

My fear of dogs could be 〜d to one of my childhood experiences.

我对狗的恐惧可以追溯到我的一次童年经历。

5.The question is how what you have learned can be put into practice.

【参考译文】问题是如何将你已经习得的知识付诸实践。

【结构分析】 The question is how what you have learned can be put into practice.此句中，特殊疑问词how引导名词性从句，和前面的The question is形成主系表结构，作句子的表语 (即表语从句在此从句中，需关注両线部分，它是特殊疑问词what引导的名词性从句，在表语从句中充当主语的成分(即主语从句），其谓语是can be put，句末的into practice是地点状语，修饰 put。

【知识链接】put...into practice把......付诸实施。

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