在雅思考试中这两种方法具体的做法是：首先，在略读时，要花足够的时间去读段落的第一句和第二句，直到完全理解作者的含义，因为第一句往往是该段的主题句（top sentence），而第二句往往是对前句的延伸（extension）或进一步的解释（explanation）。然后，运用扫描，迅速浏览从第三句开始的后面部分，搜寻作者对开头两句的支持句（supporting sentences），并同时注意文章中间是否有转折词（transition），因为这些词常常会把文章的思路逆转或加入其它重要的信息。最后，当读到段落的最后一句时，我们又要使用略读，这时必须再次放慢速度（slow down your pace）直到完全消化作者对段落的小结（conclusion），因为该小结有可能与主题句截然相反或引导读者进入下一个段落。
我们通过下面的例子来看略读与扫描在是选择段落主题句中的运用。
段落： Tourism， holiday-making and travel are these days more significant social phenomena than most commentators have considered. On the face of it there could not be a more trivial subject for a book. And indeed since social scientists have had considerable difficulty explaining weightier topics， such as work or politics， it might be thought that they would have great difficulties in accounting for more trivial phenomena such as holiday-making. However， there are interesting parallels with the study of deviance. This involves the investigation of bizarre and idiosyncratic social practices， which happen to be defined as deviant in some societies but not necessarily in others. The assumption is that the investigation of deviance can reveal interesting and significant aspects of “normal” societies. It could be said that a similar analysis can be applied to tourism。
题目： Which one of the following phrases can be the heading of the above paragraph？
选项：
i The politics of tourism
ii The cost of tourism
iii Justifying the study of tourism
iv Tourism contrasted with travel
v The essence of modern tourism
vi Tourism versus leisure
ix Creating an alternative to the everyday experience
viii The role of modern tour guides
vii The artificiality of modern tourism
解题：在这篇谈旅游业的段落中，作者第一句和第二句都使用了比较级（more significant than.。.， there could not be a more trivial.。。），这时我们要充分理解作者的含义：表面上（on the face of it）是说旅游业不是一个重要的话题，实际上暗示出旅游业的重要性，为下文的反驳打好铺垫。随后的支持句进行进一步的展开，讲探讨旅游业的困难性，似乎对于旅游业的论述是极其艰难的。然而，文章中的However使思路陡然一转，随后把对旅游业的研究与对deviance的研究作了一个对比，最后得出的结论是认为研究旅游业是同样有趣和重要的。通过这样的略读和扫描的结合，我们很容易地得出答案为iii Justifying the study of tourism，其中justify意为 “为。。。辩护，证明。。。有理”。
