以下是gre阅读长难句实例分析。gre长难句一直都是考生比较头疼的一个问题，不是因为gre考试专门考察这部分，而是在gre阅读中需要明白这些长难句才能理解整篇文章的意思。
1. Historians such as Le Roy Ladurie have used the documents to extract case histories， which have illuminated the attitudes of different social groups and have revealed how the authorities administered justice. 一类的史学家利用这些文献史料从中挖掘出某些个案史来，阐明了不同社会群体的态度，并揭示出当局是如何执行审判的。
解释：逗号以后的内容都是修饰逗号以前的case history的。在which引导的非限定性定语从句中有一个插入语，我们可以看到这个插入语中又套了一个插入语but not confined to。
意群训练：Historians such as Le Roy Ladurie have used the documents to extract case histories， which have illuminated the attitudes of different social groups and have revealed how the authorities administered justice.
2. It can be inferred from the passage that a historian who wished to compare crime rates per thousand in a European city in one decade of the fifteenth century with crime rates in another decade of that century would probably be most aided by better information about which of the following?
难句类型：复杂修饰
译文：从文章中可以推断出来，一个希望比较十五世纪以前一个十年的某个欧洲城市中的每千人的犯罪率与另外一个十年中的犯罪率的历史学家将会被以下那种信息的提高所最好的帮助?
解释：句首的it是形式主语，其具体内容是从that开始到句子结束的全部内容。That从句中，主语a historyian之后修饰它的超长的定语从句是这个句子难以读懂的原因。Compare crime rates with crime rates中间被修饰第一个crime rates的两个修饰成分perthousand in a European city in one decade of the fifteenth century分隔得很远。在with之后的第二个crime rates后面，省略了与前面重复的per thousand in a European city。
意群训练：It can be inferred from the passage that a historian who wished to compare crime rates per thousand in a European city in one decade of the fifteenth century with crime rates in another decade of that century would probably be most aided by better information about which of the following?
gre阅读长难句的并不是一天两天就能解决的，需要考生的坚持和日常的积累。