公交车短裙挺进太深了h女友,国产亚洲精品久久777777,亚洲成色www久久网站夜月,日韩人妻无码精品一区二区三区

233??У- ????????????

????
您現在的位置:233網校 >> 英語四級考試 >> 聽力 >> 聽力模擬試題 >> 文章內容

2014年英語四級聽力練習:慢速VOA(6.10)

  From VOA Leaning English, this is the Agriculture Report.

  The United Nations says the world's population will increase by 34 percent by the year 2050. Scientists and others know it will be difficult to meet the food needs of so many people. A recent study shows that soybean crops and computers may help deal with the problem.

  The U.N. predicts food production must increase by 70 percent to meet the needs of a richer population. The U.N. expects more people will live in cities than in rural areas. But today there is little too low increase in the productivity of major crops.

  Kenneth Quinn is the president of the World Food Prize Foundation. He says the need to increase food production is the greatest difficulty humanity has ever faced.

  "There's going to be another 2 billion people on our planet between now and 2050 and how are we going to produce enough food for them to eat?" asked Quinn.

  Darren Drewry is a scientist at the American Space Agency, NASA. He led a study of soybeans which NASA calls the world's most important protein crop. He says researchers using a  computer were surprised to find that they were able to create a soybean plant that can be both more productive and use less water.

  "We find that there are changes to the architecture of modern soybean cultivars can be made to help us improve on many of these goals," said Drewry.

  Researchers were able to increase soybean productivity by 7 percent without using more water. The computer helped researchers do work that would have taken many years in the field. The next step is to test the computer's design.

  We spoke to Stephen Long about that. He is a professor at the University of Illinois, and one of the writers of the report on the soybean study. He told us by Skype that researchers used computer program to study what would happen if they changed the way the plant grows.

  "One of the things the modeling predicted is that there's too much leaf area so we're actually removing leaves as the plant's growing to get a lower leaf area. We're also artificially modifying the angle of the leaves as well to reflect what the model predicted," said Long.

Professor Long says it is important to find solutions to the predicted global food shortage before it happens. He says it will be 20 years before farmers can begin growing a more productive soybean once they have developed it.

  The study on soybeans was published in the journal Global Change Biology. The National Science Foundation, NASA and the Bill & Melinda Gates Foundation paid for the study.

  And that's the VOA Learning English Agriculture Report. I'm Caty Weaver.

  233網校英語四級老師輔導英語四級改革新題型精講班/真題解析班 點擊免費試聽>>  

  聽力練習:英語四六級改革題型聽力:VOA美國之音聽寫練習匯總 

  題型練習長篇閱讀段落匹配題練習預測作文及范文翻譯練習聽寫特訓選詞填空

責編:YYT  評論  糾錯

課程免費試聽
?γ??????? ??? ???/???? ??????? ????
????????????????????????????????? ????? ??100 / ??100 ????
???????????????????????? ????? ??100 / ??100 ????
???????????????????????? ????? ??100 / ??100 ????
??????????????????д???? ????? ??100 / ??100 ????
主站蜘蛛池模板: 庐江县| 巴彦县| 闻喜县| 兴山县| 峨边| 凤冈县| 闵行区| 浪卡子县| 溆浦县| 余干县| 灵寿县| 遂平县| 镇康县| 兴城市| 溆浦县| 宣恩县| 个旧市| 米林县| 华宁县| 山阴县| 巢湖市| 永康市| 卢氏县| 株洲县| 儋州市| 丰都县| 贡觉县| 秦安县| 西宁市| 图木舒克市| 禹州市| 秭归县| 临澧县| 庆云县| 凤阳县| 松阳县| 晋城| 怀安县| 克东县| 博乐市| 波密县|