2. 外语
  3. Global warming is already cutting substantially into potential crop yields in some countries—to such an extent that it may be a

Global warming is already cutting substantially into potential crop yields in some countries—to such an extent that it may be a

admin2013-12-13  46
问题     Global warming is already cutting substantially into potential crop yields in some countries—to such an extent that it may be a factor in the food price (1)______ that have caused worldwide stress in recent years, researchers suggest in a new study.
    Wheat yields in recent years were down by more than 10 percent in Russia and by a few percentage points (2)______ in India, France and China compared with(3)______ they probably would have been without rising(4)______, according to the study.
    Corn yields were(5)______ a few percentage points in China, Brazil and France from what would have been (6)______, said the researchers, whose findings were published in Friday’s (7)______ of the journal Science.
    Some countries saw small gains from the temperature increases, however. And in all countries, the(8)______ carbon dioxide that humans are (9)______ into the air acted as a (10)______ that encouraged plant growth,(11)______ some of the losses from rising temperatures caused by that same greenhouse gas.
     (12)______, the study’s authors found that when the gains in some countries were weighed(13)______ the losses in other countries, the overall global(14)______ of climate change has been small so far: losses of a few percentage points for wheat and corn from what they would have been (15)______ climate change. The general impact on production of rice and soybeans was(16)______, with gains in some regions entirely counterbalancing losses in others.
     (17)______ the authors of the study pointed out that temperature increases were expected to(18)______ in coming decades, making it likely that the challenges(19)______ food production will grow in a era when demand is expected to(20)_____ sharply.
(3)
选项 A、that
B、which
C、what
D、how
答案C
解析 语法题。句意为，印度、法国和中国的小麦产量跟没有受到温度升高影响时的产量相比，各下降了几个百分点。所以此处应该填一个宾语从句的引导词，由于引导词在从句中充当表语，故排除不充当成分的that、充当定语的which和充当方式状语的how，所以选what。
转载请注明原文地址:https://kaotiyun.com/show/kUFK777K
0

专业英语四级

相关试题推荐
随机试题
最新回复(0)