（新概念4）第38课：下句中的themselves指的是什么?做什么成分?Contaminationofwatersuppliesisusuallyduetopoorsanitationclosetowatersources,sewagedisposalintothesourcesthemselves,leakageofsewageintodistribution

Question

（新概念4）第38课：下句中的themselves指的是什么?做什么成分?
Contamination of water supplies is usually due to poor sanitation close to water sources,sewage disposal into the sources themselves,leakage of sewage into distribution systems or contamination with industrial or farm waste.
themselves指的是什么?是sources还是sewage disposal还是其他?做什么成分?分析一下这句中的themselves~
那个,我感觉读起来意思感觉不太舒服~能不能多举几个和这句的themselves作用与位置一样的句子?

Answer 1

是sources,这是反身代词在名词后面作同位语的用法,又如：
The books themselves are good, but it is not suitable for us.
希望我能帮助你解疑释惑.