英语语法问题， 下面句中in which 后为什么不是 in which is ...而是in which it is？

Question

One is the general atmosphere of secrecy in which it is carried out. 问:下面句中in which 后为什么不是 in which is ...而是in which it is...
另外 which 指哪一部分

Answer 1

Two factors weigh heavily
against the effectiveness of scientific research in industry. One is
the general atmosphere of secrecy in which it is carried out, the other
the lack of freedom of the individual research worker.
原文拷自从一楼，如果原文是这样的话:
译文：有两个因素强烈影响工业中科学研究的效率，其中一个就是保密性氛围，科学研究在这种氛围下执行。 （我翻译的太烂了，自己意会一下）
这里的 in which 其实就是引导的一个定语从句，本质上的作用相当于 where ， 因为in which = where 起到的是状语的作用，后面的句子不能缺少成分， 如果用 不用 it，则定语从句无主语，句子成分残缺。
希望你能理解，这是定语从句！

Answer 2

看上下文啊：
Two factors weigh heavily
against the effectiveness of scientific research in industry. One is
the general atmosphere of secrecy in which it is carried out, the other
the lack of freedom of the individual research worker.
有两个原因严重地妨碍着工业中科学研究的效率，名词为scientific research ，后面的句子中的it指的正是scientific research。

这句话等于就是

One is the general atmosphere of secrecy in which they carry it out.本回答被提问者采纳