it is not _much languge as the background that makes the book diffcult to understand.1,that 2,as 3,so 4,very我觉得123都对.不要翻译,请告诉我为什么12不对

it is not _much languge as the background that makes the book diffcult to understand.1,that 2,as 3,so 4,very我觉得123都对.不要翻译,请告诉我为什么12不对
it is not _much languge as the background that makes the book diffcult to understand.
1,that 2,as 3,so 4,very
我觉得123都对.
不要翻译,请告诉我为什么12不对

it is not _much languge as the background that makes the book diffcult to understand.1,that 2,as 3,so 4,very我觉得123都对.不要翻译,请告诉我为什么12不对
it is not so much A as B.
与其说是A,不如说是B.（对于这类so,such,as……的用法、我是直接记住的、其他看都不用看= =）

分析一下句子结构
因为有as，那么所填的词要和as能搭配
所以排除1，4
因为是否定所以用so不用as
Ps：固定用法大多了太像了
能用自己的方法理解比较好

选so
not so...as...

so many / so much 是固定搭配