there was little problem recruiting sailors to row the galleys (large ships propelled by oars)： guilds (business associations) were required to provide rowers， and through a draft system free citizens served compulsorily when called for. 这句话中有冒号的出现，阅读冒号之前的内容there was little problem;到下一句：the shortage of rowers was not serious because the demand for galleys was limited by a move to round ships (round-hulled ships with more cargo space)， with required fewer rowers. 这句中要看到的核心是not serious;再往后看到But….to be a greater and greater problem. 到这里意思应该已经一目了然了，就是讲威尼斯船业在招聘船员方面所遭遇的变迁：little problem—not serious —greater problem.

　　刚才我们讲了文章阅读部分要抓关键词，其实我们在阅读题目和选项时也是需要寻找关键词的。有些题目的选项是比较长的，四个选项看上去也差不多一段话了，所以一定要抓住关键词判断才行，如否定词、比较词和并列词。这些是快速浏览选项的第一步。再次也要看到题干和每个选项中能让我们快速定位到原文的关键词。我们还是以托福TPO25为例：

　　TPO25-1 The Surface of Mars

　　Paragraph 5 As on the Moon， the extent of large impact cratering (i.e. craters too big to have been filled in by erosion since they were formed) serves as an age indicator for the Martian surface. Age estimates ranging from four billion years for Mars’s southern highlands to a few hundred million years in the youngest volcanic areas were obtained in this way。

　　According to paragraph 5， what have scientists been able to determine from studies of large impact cratering on Mars?

　　A. Some Martian volcanoes are much older than was once thought。

　　B. The age of Mars’s surface can vary from area to area。

　　C. Large impact craters are not reliable indicators of age in areas with high volcanic activity。

　　D. Some areas of the Martian surface appear to be older than they actually are。

　　划出选项中的关键词后，定位到原文迅速浏览发现原文中并无如A和D选项中的比较，C中的否定词not和原文是明显相矛盾的，故而选择B，而B选项对应的恰好是本段末句：Age estimates ranging from four billion years for Mars’s southern highlands to a few hundred million years in the youngest volcanic areas were obtained in this way。

　　根据以上分析，我们应该明白在阅读之时何为关键词。简单地讲有定位关键词和判断关键词。定位关键词包括题干及选项中的名词，还有就是段落中那些一直向你示好的逻辑信号词了，不要忘记用它们找到你解题需要的信息。判断关键词是选项中那些有特色的词汇，包括否定词，比较词或者是句子主干中的动词等，根据这些词和原文进行对应，至少有一半的选项可以迅速被排除。

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