今天要聊的主要是關(guān)于做托福修辭目的題的小技巧，幫助學(xué)員們能夠在考試?yán)锶〉煤贸煽?

　　我們先回顧一下這種題型問法，最經(jīng)典的當(dāng)屬why does the author mention...?

　　題目通常會在段落中highlight出一個部分，問我們?yōu)槭裁醋髡咭岬侥硞€詞、某句話或者某個例子。也就是說我們需要通過題目給出的細(xì)節(jié)信息判斷出作者的寫作目的和意圖是什么，這其實也是修辭目的題的難點所在。

　　很多時候并不是只看完所提及的細(xì)節(jié)或者依靠我們自己的歸納總結(jié)就能選出正確答案，甚至只看細(xì)節(jié)反而容易被帶跑偏。它需要我們通過對句子的分析，找出真正的主旨句或者論點句在哪里。

　　技巧一、牢記作者目的經(jīng)典位置

　　我們知道常見的段落結(jié)構(gòu)有總分、分總和總分總，而在托福閱讀中先總后分的結(jié)構(gòu)比較受偏愛。

　　所以通常情況下作者目的往往出現(xiàn)在所提及信息的前面，可能是比較直接的前一句，也可能是整段的中心句，放在段首部分，需要具體情況具體分析，我們可以結(jié)合下面的例子來理解。

　　例題一：

　　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.

　　這道題就屬于作者目的在定位句前一句或者說前兩句的情況。我們可以看到包含“a telescope”的定位句以for example開頭，明顯是一個例子。

　　技巧二：巧用選項動詞排除大法

　　大部分修辭目的題的選項都是由to開始，以表示為了達(dá)到某個目的，而to后面的動詞比較容易被我們忽略，但其實仔細(xì)檢查這些動詞對于做題也是非常有幫助的。

　　例題二：

　　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

　　這道題我們就可以先來看看選項動詞，a是contrast對比，b是question質(zhì)疑，c是suggest表明，d是provide examples提供例子。

　　技巧三：巧用選項邏輯排除大法

　　選項中除了to后面的動詞對做題很有用之外，其中的邏輯關(guān)系也值得我們好好分析，經(jīng)常可以起到幫助我們縮小選擇范圍的作用。

　　例題三：

　　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.

　　這道題中定位句和前一句的關(guān)聯(lián)比較明顯。定位句出現(xiàn)了代詞they，指代的是前一句中的Hyperaccumulators，而定位句可以說在對Hyperaccumulators做一些列舉來體現(xiàn)出它的范圍廣。