英语大神帮我分析下这英语句子的结构吧

英语大神帮我分析下这英语句子的结构吧
这句话里的废话我不打了,只打主体和我不明白的
During this period,researchers from XXX interviewed nearly 3000 women,some of whom had learnt to read as children,some during the literacy crusade and some who had never learnt at all.
我想知道这句话里,逗号后面的some...,some...and some...这半句和women的关系,还有第一个,第三个some后有had,引导的定从,那第二个some后面算什么,我脑袋全晕了,