The hunter-gatherer tribes that today live as our prehistoric human __1__ancestors consume primarily a vegetable diet supplementing with animal foods __2__An analysis of 58 societies of modern hunter-gatherers, including the Kung of southern Africa, revealed that one-half emphasize gathering plants foods, one-third concentrate on fishing, and only one-sixth are primarily hunters,Overall, two-thirds and more of the hunter-gatherer’s calories come from __3__plants. Detailed studies of the Kung by the food scientists at the Universityof London, showed that gathering is a more productive source of foodthan is hunting. An hour of hunting yields in average about 100 edible __4__calories, as an hour of gathering produces 240. __5__Plant foods provide for 60 percent to 80 percent of the Kung diet, and no __6__one goes hungry when the hunt fails. Interestingly, if they escape fatal infectionsor accidents, these contemporary aborigines live to old ages despite of the absence __7__of medical care. They experience no obesity, no middle-aged spread, littledental decay, no high blood pressure, no heart disease, and their bloodcholesterol levels are very low (about half of the average American adult). __8__If no one is suggesting that we return to an aboriginal life style, we certainly __9__could use their eating habits as a model for healthier diet. __10__
參考答案及解析:
1. 將as 改爲like此處的意思是“像史前人類祖先那樣生活”。
2. 將supplementing改爲supplementedsupplemented 修飾diet，可以看作which is supplemented with animal foods的.簡化形式。
3. 將and 改爲or4. 將in改爲onon average 是固定用法。
5. 將as 改爲while或者whereas6. 刪掉for，或者將provide改爲account此處provide 是及物動詞，後面不用介詞for7. 刪掉第一個of despite 做介詞，後面直接接名詞。
8. 在half後加thatthat 指代前面的blood cholesterol levels，不能省略，因爲這裏是將部落成員的膽固醇含量與美國人的膽固醇含量相比較。
9.將if改爲whereas或者while此處意思爲“儘管沒有人……,但是……”，是轉折關係。
10.在for後面加不定冠詞a。
