今天要聊的主要是关于做托福修辞目的题的小技巧，帮助学员们能够在考试里取得好成绩!
我们先回顾一下这种题型问法，最经典的当属why does the author mention...?
题目通常会在段落中highlight出一个部分，问我们为什么作者要提到某个词、某句话或者某个例子。也就是说我们需要通过题目给出的细节信息判断出作者的写作目的和意图是什么，这其实也是修辞目的题的难点所在。
很多时候并不是只看完所提及的细节或者依靠我们自己的归纳总结就能选出正确答案，甚至只看细节反而容易被带跑偏。它需要我们通过对句子的分析，找出真正的主旨句或者论点句在哪里。
技巧一、牢记作者目的经典位置
我们知道常见的段落结构有总分、分总和总分总，而在托福阅读中先总后分的结构比较受偏爱。
所以通常情况下作者目的往往出现在所提及信息的前面，可能是比较直接的前一句，也可能是整段的中心句，放在段首部分，需要具体情况具体分析，我们可以结合下面的例子来理解。
例题一：
Magnification, the increase in the apparent size of an object, is one important factor in microscopy. Also important is resolving power, a measure of the clarity of an image. Resolving power is the ability of an optical instrument to show two objects as separate. For example, what looks to the unaided eye like a single star in the sky may be resolved as two stars with the help of a telescope. Any optical device is limited by its resolving power. The light microscope cannot resolve detail finer than 0.2 micrometers, about the size of the smallest bacterium; consequently, no matter how many times its image of such a bacterium is magnified, the light microscope cannot show the details of the cell's internal structure.
2.Why does the author mention "a telescope" as part of the discussion of microscopes?
A. To show how microscopes and telescopes are different.
B. To emphasize the importance of magnification in all optical devices.
C. To explain how the development of the microscope depended on the invention of the telescope.
D. To illustrate the concept of resolving power.
这道题就属于作者目的在定位句前一句或者说前两句的情况。我们可以看到包含“a telescope”的定位句以for example开头，明显是一个例子。
技巧二：巧用选项动词排除大法
大部分修辞目的题的选项都是由to开始，以表示为了达到某个目的，而to后面的动词比较容易被我们忽略，但其实仔细检查这些动词对于做题也是非常有帮助的。
例题二：
A third fossil formation containing both soft-bodied and hard-bodied animals provides evidence of the result of the Cambrian explosion. This fossil formation, called the Burgess Shale, is in Yoho National Park in the Canadian Rocky Mountains of British Columbia. Shortly after the Cambrian explosion, mud slides rapidly buried thousands of marine animals under conditions that favored fossilization. These fossil beds provide evidence of about 32 modern animal groups, plus about 20 other animal body forms that are so different from any modern animals that they cannot be assigned to any one of the modern groups. These unassignable animals include a large swimming predator called Anomalocaris and a soft-bodied animal called Wiwaxia, which ate detritus or algae. The Burgess Shale formation also has fossils of many extinct representatives of modern animal groups. For example, a well-known Burgess Shale animal called Sidneyia is a representative of a previously unknown group of arthropods (a category of animals that includes insects, spiders, mites, and crabs).
10. Why does the author mention “Anomalocaris” and “Wiwaxia”?(4)
○ To contrast predators with animals that eat plants such as algae
○ To question the effects of rapid mud slides on fossilization
○ To suggest that much is still unknown about animals found in the Burgess Shale
○ To provide examples of fossils that cannot be assigned to a modern animal group
这道题我们就可以先来看看选项动词，a是contrast对比，b是question质疑，c是suggest表明，d是provide examples提供例子。
技巧三：巧用选项逻辑排除大法
选项中除了to后面的动词对做题很有用之外，其中的逻辑关系也值得我们好好分析，经常可以起到帮助我们缩小选择范围的作用。
例题三：
Scientists have known for some time that certain plants, called hyperaccumulators, can concentrate minerals at levels a hundredfold or greater than normal. A survey of known hyperaccumulators identified that 75 percent of them amassed nickel, cobalt, copper, zinc, manganese, lead, and cadmium are other minerals of choice. Hyperaccumulators run the entire range of the plant world. They may be herbs, shrubs, or trees. Many members of the mustard family, spurge family, legume family, and grass family are top hyperaccumulators. Many are found in tropical and subtropical areas of the world, where accumulation of high concentrations of metals may afford some protection against plant-eating insects and microbial pathogens.
8. Why does the author mention “herbs”, “shrubs”, and “trees”? (4)
○ To provide examples of plant types that cannot tolerate high levels of harmful minerals.
○ To show why so many plants are hyperaccumulators.
○ To help explain why hyperaccumulators can be found in so many different places.
○ To emphasize that hyperaccumulators occur in a wide range of plant types.
这道题中定位句和前一句的关联比较明显。定位句出现了代词they，指代的是前一句中的Hyperaccumulators，而定位句可以说在对Hyperaccumulators做一些列举来体现出它的范围广。 |
