抓住句子的结构是十分重要的，有些句子的并列结构是我们需要敏锐的看出的（在SAT 文法题中考察对并列成分的抓取），比如在官方指南上的一篇阅读文章Artisans and Industrialization 的一句话就有比较复杂的并列结构，这句话介绍了19世纪美国学徒Apprentice和匠人师傅之间的关系：
Apprentices were considered part of the family, and masters were responsible not only for teaching their apprentices a trade but also for providing them some education and for supervising their moral behavior.

生词积累
1. Supervise: v. 监督，近义词 oversee
2. Moral: adj 道德的
 
总体来说，这个句子是个并列句。前半部分：Apprentices were considered part of the family 就是说学徒被当做（师傅的）家人。（是不是和我们中国很像）
 
我们关键看看这个句子的后半句 masters were responsible not only for teaching their apprentices a trade but also for providing them some education and for supervising their moral behavior. 这句话有很多 for 引导的短语，这会使得一些同学们感到头疼。
 
大家还要抓住并列结构 not only, but also, and 并且明白它们的功能是连接意义相关、层次相同、语法结构也相同的结构。那么这三个 for 引导的介词短语，它们的层次和语法结构都相同，很明显都是并列关系。大家需要注意，有时候并列关系不仅仅是并列两项，还有可能并列多项。我们把并列关系都标出来，结构如下：
 
masters were responsible not only for teaching their apprentices a trade but also for providing them some education and for supervising their moral behavior.

我们知道 be responsible for （对……负责）的结构，并且三个for引导的介词短语是并列关系。所以这句话讲解的是师傅要对三件事情负责。句子含义是：师傅对教学徒一个行业、提供学徒一定的教育和监管他们的道德行为负责。