Unfortunately,space being spacious,the average distance betw

不幸的是,空间浩瀚,任何两个文明社会之间的平均距离据测算至少在200光年,而这个（空间如此的浩瀚的概念）超出了所能用言语表达的范围.
which 后面一个非限定性定语从句,指代前面的那个句子,因此,我用而这个（空间如此的浩瀚的概念）来概括
more than merely saying ,有点像,i love you more than i can say 的表达,只不过,这里的than 做介词,因此用了saying 动名词,i love you more than i can say 的than 做了连词,因此用了句子
it makes it sound是say 的宾语部分,字面意思是就是超过他听上去的这么的浩瀚,需要意译

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