托福閱讀真題Official 52 Passage 3（七）

托福閱讀真題Official 52 Passage 3（七）

Early Food Production in Sub-Saharan Africa

At the end of the Pleistocene(around 10,000 B.C.),the technologies of food production may have already been employed on the fringes of the rain forests of western and central Africa,where the common use of such root plants as the African yam led people to recognize the advantages of growing their own food.The yam can easily be resprouted if the top is replanted.This primitive form of“vegeculture”(cultivation of root and tree crops)may have been the economic tradition onto which the cultivation of summer rainfall cereal crops was grafted as it came into use south of the grassland areas on the Sahara’s southern borders.

As the Sahara dried up after 5000 B.C.,pastoral peoples(cattle herders)moved southward along major watercourses into the savanna belt of West Africa and the Sudan.By 3000 B.C.,just as ancient Egyptian civilization was coming into being along the Nile,they had settled in the heart of the East African highlands far to the south.The East African highlands are ideal cattle country and the home today of such famous cattle-herding peoples as the Masai.The highlands were inhabited by hunter-gatherers living around mountains near the plains until about 3300 B.C.,when the first cattle herders appeared.These cattle people may have moved between fixed settlements during the wet and dry seasons,living off hunting in the dry months and their own livestock and agriculture during the rains.

As was the case elsewhere,cattle were demanding animals in Africa.They required water at least every 24 hours and large tracts of grazing grass if herds of any size were to be maintained.The secret was the careful selection of grazing land,especially in environments where seasonal rainfall led to marked differences in graze quality throughout the year.Even modest cattle herds required plenty of land and considerable mobility.To acquire such land often required moving herds considerable distances,even from summer to winter pastures.At the same time,the cattle owners had to graze their stock in tsetse-fly-free areas.The only protection against human and animal sleeping sickness,a disease carried by the tsetse fly,was to avoid settling or farming such areas—a constraint severely limiting the movements of cattle-owning farmers in eastern and central Africa.As a result,small cattle herds spread south rapidly in areas where they could be grazed.Long before cereal agriculture took hold far south of the Sahara,some hunter-gatherer groups in the savanna woodlands of eastern and southern Africa may have acquired cattle,and perhaps other domesticated animals,by gift exchange or through raids on herding neighbors.

Contrary to popular belief,there is no such phenomenon as“pure”pastoralists,a society that subsists on its herds alone.The Saharan herders who moved southward to escape drought were almost certainly also cultivating sorghum,millet,and other tropical rainfall crops.By 1500 B.C.,cereal agriculture was widespread throughout the savanna belt south of the Sahara.Small farming communities dotted the grasslands and forest margins of eastern West Africa,all of them depending on what is called shifting agriculture.This form of agriculture involved clearing woodland,burning the felled brush over the cleared plot,mixing the ash into the soil,and then cultivating the prepared fields.After a few years,the soil was exhausted,so the farmer moved on,exploiting new woodland and leaving the abandoned fields to lie fallow.Shifting agriculture,often called slash-and-burn,was highly adaptive for savanna farmers without plows,for it allowed cereal farming with the minimal expenditure of energy.

The process of clearance and burning may have seemed haphazard to the uninformed eye,but it was not.Except in favored areas,such as regularly inundated floodplains,tropical Africa’s soils were of only moderate to low fertility.The art of farming was careful soil selection,that is,knowing which soils were light and easily cultivable,could be readily turned with small hoes,and would maintain their fertility over several years’planting,for cereal crops rapidly remove nitrogen and other nutrients from the soil.Once it had taken hold,slash-and-burn agriculture expanded its frontiers rapidly as village after village took up new lands,moving forward so rapidly that one expert has estimated it took a mere two centuries to cover 2,000 kilometers from eastern to southern Africa.

Question 13 of 14

Look at the four squares[■]that indicate where the following sentence could be added to the passage.Southern Africa was,however,relatively free of tsetse flies.Where would the sentence best fit?Click on a square[■]to add the sentence to the passage.

正確答案：C

題目詳解

題型分類：插入句子題

題干分析：考察句子和句子之間的銜接判斷（通過(guò)however這一轉(zhuǎn)折詞匯，可以預(yù)測(cè)出前面講過(guò)某些地區(qū)存在舌蠅，后面有可能講南部地區(qū)舌蠅少所造成的影響）。

選項(xiàng)分析：

C選項(xiàng)however與前一句eastern and central Africa存在tsetse flies形成轉(zhuǎn)折。并且與后一句As a result，small cattle herds spread south形成因果邏輯。

A選項(xiàng)邏輯錯(cuò)誤，后一句graze their stock和前一句都在說(shuō)放牧對(duì)土地的要求，該處不能插句子。

B選項(xiàng)邏輯錯(cuò)誤，后一句a disease carried by the tsetse fly解釋了前一句需要在tsete-fly-area放牧的原因，該處不能插句子。

D選項(xiàng)邏輯錯(cuò)誤，后一句south of the Sahara與前一句spread south呼應(yīng)，該處不能插句子。

Question 14 of 14

Directions:An introductory sentence for a brief summary of the passage is provided below.Complete the summary by selecting the THREE answer choices that express the most important ideas in the passage.Some sentences do not belong in the summary because they express ideas that are not presented in the passage or are minor ideas in the passage.This question is worth 2 points.

The technologies of food production may have already been employed by some sub-Saharan peoples by the end of the Pleistocene.

Answer Choices:

A.

Food production started with the cultivation of root plants and developed to include the cultivation of cereal crops.

B.

Pastoralists who moved south across the Sahara to find suitable land for cattle grazing may have also cultivated some crops for food.

C.

In order to avoid human and animal sleeping sickness,which posed a danger to herders and cattle,more and more herders took up cultivation.

D.

Hunter-gatherer groups in eastern and southern Africa raided their herding neighbors to acquire cattle and other domesticated animals.

E.

By 1500 B.C.cereal agriculture was widespread throughout the savanna belt south of the Sahara,and shifting agriculture was used effectively and widely by farmers.

F.

Slash-and-burn agriculture was initially rejected by farmers because it was too labor-intensive,but once the technique was improved,it expanded gradually to eastern and southern Africa.

正確答案：ABE

題目詳解

題型分類：文章總結(jié)題

題干分析：選擇概括性的正確選項(xiàng)。

選項(xiàng)分析：

A選項(xiàng)對(duì)應(yīng)第一段重要信息。最后一句cultivation of root對(duì)應(yīng)選項(xiàng)中的cultivation of root plants；cultivation of summer rainfall cereal crops對(duì)應(yīng)選項(xiàng)中的cultivation of cereal crops。

B選項(xiàng)對(duì)應(yīng)第四段重要信息，第2句moved southward to escape drought對(duì)應(yīng)選項(xiàng)中的moved south across the Sahara to find suitable land；cultivating sorghum,millet,and other tropical rainfall crops對(duì)應(yīng)選項(xiàng)中的cultivated some crops for food。

E選項(xiàng)對(duì)應(yīng)第四，五段重要信息，第四段第3句By 1500 B.C.,cereal agriculture was widespread throughout the savanna belt south of the Sahara對(duì)應(yīng)選項(xiàng)By 1500 B.C.cereal agriculture was widespread throughout the savanna belt south of the Sahara，第五段最后一句slash-and-burn agriculture expanded its frontiers rapidly...moving forward so rapidly對(duì)應(yīng)選項(xiàng)shifting agriculture was used effectively and widely by farmers。

C選項(xiàng)出自第四段第一句，但原文說(shuō)的是there is no such phenomenon as“pure”pastoralists，說(shuō)明放牧和種植并行，而不是more and more herders took up cultivation，與原文矛盾。

D選項(xiàng)出自第三段最后一句話，為第三段細(xì)節(jié)。

F選項(xiàng)出自第四段最后一句話，但原文說(shuō)的是highly adaptive for savanna farmers without plows...with the minimal expenditure of energy，而不是too labor-intensive與原文矛盾。

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