It is only in the study of man himself that the major social sciences have substituted(未完，下面有

It is only in the study of man himself that the major social sciences have substituted(未完，下面有

主要社会科学被本地变化代替
主要社会科学被本地变化代替，本句是个强调句：It is +被强调的成分+that+其他成分，去掉it is..that,
in the study of man himself ，the major social sciences have substituted the study of one local variation.
在人类自身研究方面，主要社会科学被本地变化代替

主要社会科学的研究仅仅在人类本身的学习上已经代替了本地差异和西方文明。（这是一个强调句.形式是It is +被强调的成分+that+其他成分）。本句强调的是状语in the study of man himself.
希望能帮到你。追问这是新概念英语第四册第44课倒数第二段的最后一句话，有翻译，但谁代替谁翻的让我不理解。你如果愿意可以看一下。anyway ,thank you.追答社会科学的研究代替了本地差异和西方文明的研究