第一节 同义替换

一、考点介绍

同义替换是雅思阅读A类考试中的一个重要考点，各种题型中都会出现。在Cambridge IELTS 9的160道A类阅读题目中，绝大部分的题目都涉及了同义替换。

这种考点的出题思路就是题目和（或）选项中的关键词或词组在原文材料中往往以同义替换的形式出现。最常见的替换有两种：

一是同义词替换。这是雅思阅读A类考试中最常出现的，比如，题目中的关键词是survive，在原文中该词有可能被替换成avoid dying out。

二是词性的替换。比如，题目中的关键词是explain，在原文中该词有可能被替换成explanation。

同义替换在雅思考试中无处不在，《雅思周计划——词汇》一书专门收录了近年来雅思考试中经常出现的重点词汇及其同反义词，要求考生熟练掌握。

二、真题示例

Example 1（Cambridge IELTS 9 Test 1 READING PASSAGE 3 Questions 31-33）

【真题回顾】

READING PASSAGE 3

The history of the tortoise

If you go back far enough, everything lived in the sea. At various points in evolutionary history, enterprising individuals within many different animal groups moved out onto the land, sometimes even to the most parched deserts, taking their own private seawater with them in blood and cellular fluids. In addition to the reptiles, birds, mammals and insects which we see all around us, other groups that have succeeded out of water include scorpions, snails, crustaceans such as woodlice and land crabs, millipedes and centipedes, spiders and various worms. And we mustn't forget the plants, without whose prior invasion of the land none of the other migrations could have happened.

Moving from water to land involved a major redesign of every aspect of life, including breathing and reproduction. Nevertheless, a good number of thoroughgoing land animals later turned around, abandoned their hard-earned terrestrial re-tooling, and returned to the water again. Seals have only gone part way back. They show us what the intermediates might have been like, on the way to extreme cases such as whales and dugongs. Whales (including the small whales we call dolphins) and dugongs, with their close cousins the manatees, ceased to be land creatures altogether and reverted to the full marine habits of their remote ancestors. They don't even come ashore to breed. They do, however, still breathe air, having never developed anything equivalent to the gills of their earlier marine incarnation. Turtles went back to the sea a very long time ago and, like all vertebrate returnees to the water, they breathe air. However, they are, in one respect, less fully given back to the water than whales or dugongs, for turtles still lay their eggs on beaches.

There is evidence that all modern turtles are descended from a terrestrial ancestor which lived before most of the dinosaurs. There are two key fossils called Proganochelys quenstedti and Palaeochersis talampayensis dating from early dinosaur times, which appear to be close to the ancestry of all modern turtles and tortoises. You might wonder how we can tell whether fossil animals lived on land or in water, especially if only fragments are found. Sometimes it's obvious. Ichthyosaurs were reptilian contemporaries of the dinosaurs, with fins and streamlined bodies. The fossils look like dolphins and they surely lived like dolphins, in the water. With turtles it is a little less obvious. One way to tell is by measuring the bones of their forelimbs.

【考点点拨】

31 Turtles were among the first group of animals to migrate back to the sea.

答案：NOT GIVEN

关键词：turtles、first、migrate back to the sea

定位句：根据关键词定位到第二段倒数第四行：Turtles went back to the sea a very long time ago and, like all vertebrate returnees to the water, they breathe air．海龟在很久以前就返回了海洋，而如同其他所有返回水中的脊椎动物一样，它们也呼吸空气。

解析：题目中的关键词turtles在定位句中重现，定位句中的went back to the sea和题目中的migrate back to the sea是同义替换，定位句对返回时间的描述是a very long time ago，但并没有说是不是the first group，答案就是NOT GIVEN。

考点：同义替换。went back to the sea = migrate back to the sea。

32 It is always difficult to determine where an animal lived when its fossilised remains are incomplete.

答案：FALSE

关键词：difficult to determine、fossilised remains、incomplete

定位句：根据关键词定位到第三段第四行：You might wonder how we can tell whether fossil animals lived on land or in water, especially if only fragments are found. Sometimes it's obvious．你也许会怀疑我们是如何通过动物化石来判断它们是生活在水中还是陆地上的，尤其是只找到一些化石碎片的时候。有时候很明显。

解析：定位句中的fossil、fragments和分别题目中的fossilised remains、incomplete是同义替换，定位句中的obvious（明显的）和题目中的difficult to determine意思相反，答案就是FALSE。

考点：同义替换。fossil = fossilised remains; fragments = incomplete。

33 The habitat of ichthyosaurs can be determined by the appearance of their fossilised remains.

答案：TRUE

关键词：determined、appearance of their fossilised remains

定位句：根据关键词定位到第三段倒数第三行：The fossils look like dolphins and they surely lived like dolphins, in the water．它们的化石看起来像海豚，并且确信无疑的是，它们也像海豚一样生活在水里。

解析：定位句中的fossils look like、surely分别和题目中的appearance of their fossilised remains、determined是同义替换，答案就是TRUE。

考点：同义替换。fossils look like = appearance of their fossilised remains; surely =determined。

Example 2（Cambridge IELTS 8 Test 1 READING PASSAGE 2 Questions 20 and 21）

【真题回顾】

READING PASSAGE 2

AIR TRAFFIC CONTROL IN THE USA

A An accident that occurred in the skies over the Grand Canyon in 1956 resulted in the establishment of the Federal Aviation Administration (FAA) to regulate and oversee the operation of aircraft in the skies over the United States, which were becoming quite congested. The resulting structure of air traffic control has greatly increased the safety of flight in the United States, and similar air traffic control procedures are also in place over much of the rest of the world.

B Rudimentary air traffic control (ATC) existed well before the Grand Canyon disaster. As early as the 1920s, the earliest air traffic controllers manually guided aircraft in the vicinity of the airports, using lights and flags, while beacons and flashing lights were placed along cross-country routes to establish the earliest airways. However, this purely visual system was useless in bad weather, and, by the 1930s, radio communication was coming into use for ATC. The first region to have something approximating today's ATC was New York City, with other major metropolitan areas following soon after.

【考点点拨】

20 The FAA was created as a result of the introduction of the jet engine.

答案：FALSE

关键词：FAA、as a result of、jet engine

定位句：根据关键词定位到A段第一行：An accident that occurred in the skies over the Grand Canyon in 1956 resulted in the establishment of the Federal Aviation Administration (FAA). 1956年发生在（美国）大峡谷上空的一起事故促成了联邦航空管理局（FAA）的成立。

解析：题目说的是FAA … as a result of … jet engine，而定位句说的是accident …resulted in … FAA；题目和定位句对FAA出现原因的描述不一致，答案就是FALSE。

考点：同义替换。resulted in = as a result of。

21 Air Traffic Control started after the Grand Canyon crash in 1956.

答案：FALSE

关键词：Air Traffic Control、after、Grand Canyon crash

定位句：根据关键词定位到B段第一行：Rudimentary air traffic control (ATC) existed well before the Grand Canyon disaster．早在大峡谷灾难发生之前，基本的航空交通管制（ATC）就已经存在了。

解析：题目中的关键词Air Traffic Control在定位句中重现，后面说的是before the Grand Canyon disaster，而题目说的是after the Grand Canyon crash。定位句中的disaster和题目中的crash是同义替换，题目和定位句所说的时间相反，答案就是FALSE。

考点：同义替换。disaster = crash。