15-6. Yet a great many processes depending on such research are sought for with complete secrecy until the stage at which patents can be taken out.

【译文】然而，依赖这种研究的很多程序是在完全保密情况下进行的，直到可以获得专利的阶段为止。

【讲解】depending on such research作定语，修饰processes。with complete secrecy作状语，修饰are sought for。at which patents can be taken out系定语从句，修饰stage。

【单词和短语】

patent: 专利，专利权，专利证书（a special document that gives you the right to make or sell a new invention or product that no one else is allowed to copy），

例如：
take out a patent for an invention 取得一项发明的专利
hold a patent on 对……拥有专利权

Patents have been running out on these drugs.
这些药的专利权正在陆续到期。

patent亦可作动词（参见下句），意为“得到……的专利权（to obtain a special document giving you the right to make or sell a new invention or product）”，

例如：
The company has patented many new inventions.
这家公司得到了许多新发明的专利权。

15-7. Even more processes are never patented at all but kept as secret processes.

【译文】甚至更多的工艺过程根本就不获得专利，而是都作为秘方保存。

【讲解】句中的never…but…，相当于not…but…，只是前者用了never表示强调；never…but…在这里连接两个并列的被动语态的动词are patented和（are）kept，作“从不……而（是）解”。but后省略了are。

【单词和短语】参见上句对patent的讲解。

15-8. This applies particularly to chemical industries, where chance discoveries play a much larger part than they do in physical and mechanical industries.

【译文】化学工业尤其如此。因为在化学工业中，偶然性发现所起的作用要比在物理工业和机械工业中所起的作用大得多。

【讲解】this指上句内容，可简要译为“保密”。they指chance discoveries。do代替play a part。where chance discoveries…mechanical industries系非限制性定语从句，修饰chemical industries。

【单词和短语】

chance：偶然的，碰巧的，意想不到的（not planned or expected），

例如：
a chance decision 偶然的决定
a chance meeting 邂逅
a chance visitor 不速之客

apply：请参见第八课第13句对apply讲解。

15-9. Sometimes the secrecy goes to such an extent that the whole nature of the research cannot be mentioned.

【译文】有时保密竟达到了连研究工作的整个性质都不准提及的程度。

【讲解】that the whole nature…mentioned是结果状语从句。

15-10. Many firms, for instance, have great difficulty in obtaining technical or scientific books from libraries because they are unwilling to have their names entered as having taken out such and such a book, for fear the agents of other firms should be able to trace the kind of research they are likely to be undertaking.

【译文】例如，很多公司向图书馆借阅科技书籍时感到困难，因为它们不愿让人家知道某个公司借了某本书。它们生怕其他公司的情报人员据此摸到他们正在从事的科研项目。

【讲解】as having taken out such and such a book是介词短语，作entered的方式状语。as是介词，having taken out是动名词短语taking out的完成时结构。such and such a book，某本书，英语中不指名地提到某个人时这样表示：Mr. so and so，不具体说出某人或某事的名字或特征时，则说：such and such a man（place，date，etc.）

【单词和短语】

for fear起连词作用，fear后省略了that，引导目的状语从句。这从句中常用虚拟语气。

又如：
He handled the instrument with care for fear（that）it should be damaged.

他小心翼翼地处置这仪器，生怕给弄坏了。

lest与for fear同义，只是较为古雅，多用于正式文体中。