2017年10月21日雅思阅读考试前考生可以将本文为大家提供的机经资料进行重点练习，尤其是阅读背景知识以及核心词汇。下面一起来看2017年10月21日雅思阅读机经预测小范围版资料内容，希望为备考的同学提供更多有效的信息。
题材 动物
题型 判断 6+填空 7
文章大意 讲了鱼类的交流，德国科学家在红海发现红色的鱼，发现是激发荧光。鱼用这个荧光来识别种群、标识位置、吓退敌人、掩盖自己和捕捉猎物。
参考阅读：
Fish Communication
The answer to both questions is yes, but fish "talk" and "hear" somewhat differently than humans. Although not extremely common, there are several species of fish that are able to produce sound to communicate with members of their own and other species. Most of the fish that produce sound do it at such low frequencies that divers cannot hear the noises. But several species do produce sound in the range that humans can hear. For example, grunts are able to produce sound by grinding their flat teeth together (hence the name grant!) The large Jewfish, Nassau and Black groupers are known to make very loud "booms" when startled or cornered. Jewfish have also been observed to make these loud sounds during courtship.
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题型 判断+流程图+简答
文章大意 古希腊钱币。介绍了硬币的制造过程，生产工艺及当时的时代背景。
参考阅读： The history of Ancient Greek coinage can be divided (along with most other Greek art forms) into four periods, the Archaic, the Classical, the Hellenistic and the Roman. The Archaic period extends from the introduction of coinage to the Greek world during the 7th century BC until the Persian Wars in about 480 BC. The Classical period then began, and lasted until the conquests of Alexander the Great in about 330 BC, which began the Hellenistic period, extending until the Roman absorption of the Greek world in the 1st century BC. The Greek cities continued to produce their own coins for several more centuries under Roman rule. The coins produced during this period are called Roman provincial coins or Greek Imperial Coins.
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题材 能源
题型 选择 3+配对 5+句子填空 5
文章大意 本文介绍了各种海洋资源，包括了潮汐能、洋流能、波浪能和海底热能。。
部分答案参考：
选择
在海洋中建立 Tidal power plant 的 positive effects?
A. A range of sea shore
B. cost of establishing a tidal power plant
C. it is helpful to establish transportation system
D. effect of fish and some other sea life around
配对题
A. Tidal energy
B. Current energy
C. Thermal energy
1. which kind of energy has already been subject to a successful trial A
2. A
3. Which kind of energy has been largely used during the past time? B
4. Which kind of energy has failed in an experiment? C
摘要总结题
1. Water, above 30 ℃, will be 冲到水底产生能量
2. ammonia
3. 热能机制里用到了水冲刷 turbine 的原理
4. 深度是海底 500 米
题材 发展史
题型 段落信息配对题 5+多选题 2+判断题 6
文章大意 介绍了纸币的发展史，纸币是如何从硬币发展成纸币的，以及历史上的一些制造方法和未来的趋势。
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