2.Distinguish between general and specific informaton

段落中的概括性信息经常是一般的, 普通的, 综合的, 概括的, 全面的, 大体上的的归纳和总结。段落中的细节性信息是对概括性原则、规律、判断及陈述的展开和细化，表现为举例、分类、阶段性描述或者举证。所以，概括性信息通常是重点信息。

概括性信息不必然在段首或者段尾出现，这时就给考生的阅读能力提出了挑战。有一种办法不一定总是有效，但是一旦掌握，对于把握重点信息还是有很大帮助的。就是比较段落当中名词概念的种属关系。通常而言，属概念所在的句子是概括性信息，种概念所在的句子是细节性信息。找到概括性信息并仔细阅读是正确处理list of headings 的关键。

Through the ages, great floods alternated with long periods of drought have assaulted people and their environment, hampering their fragile fight for survival. The dramatic changes to the environment that are now a feature of our daily news are not exactly new: fields that were once teeming with life are now long gone; savannah has been turned to desert. What perhaps is new is our naive wonder when faced wifth the forces of nature.

就以上段落给出了两个待选的headings：1、The destructive force of water in former times. 2. Environmental change has always been with us（正确）

尽管Through the ages与former times在时间上相呼应，尽管assaulted 和hampering 与destructive force 在语义上相呼应，但是，与The dramatic changes to the environment 相比较，great floods 和drought是两个细节性概念，表明第一句话是细节性的。第二句话才是概括性的。因为，洪水和干旱是急剧的环境变化的具体表现，是后者的种概念。