2. 外语
  3. To many web-building spiders, most of 【C1】______ are nearly blind, the web is their essential window 【C2】______ the world: thei

To many web-building spiders, most of 【C1】______ are nearly blind, the web is their essential window 【C2】______ the world: thei

admin2010-03-19  14
问题      To many web-building spiders, most of 【C1】______  are nearly blind, the web is their essential window 【C2】______ the world: their means of communicating, 【C3】______ prey, meeting mates and protecting themselves. A web-building spider 【C4】______ its web is like a man marooned on an island of solid rock, totally out of touch and destined to starve to death. So 【C5】______ is the web to an orb-web spider’s survival that the animal will continue to construct new webs daily 【C6】______ it is being starved.
     For 16 days the 【C7】______ spider builds completely normal webs. Then, as the animal gets scrawnier, it constructs a wider-meshed web using 【C8】______ strands. Such webs would only trap larger prey, which is more 【C9】______  from the perspective of a starving spider.
     The spider 【C10】______ energy by recycling web protein. It simply eats its own web each evening and reuses it to manufacture 【C11】______ silk. In studies with radioactively labeled materials, it 【C12】______ that 95 percent of web protein reappeared in 【C13】______ web. Most of the energy needed for web-building is used in walking over the strands as they are laid down.
     Scientists are 【C14】______ by the adaptability of the spider’s highly preprogrammed brain, which is larger 【C15】______  its size than the brain of any other invertebrate. If web-building is interrupted, or if some of the 【C16】______ strands are destroyed, the spider 【C17】______ retraces its steps to see where the web is 【C18】______ and then finishes building a 【C19】______ web. One spider will even finish building the incomplete web of 【C20】______ .
【C6】
选项 A、if
B、when
C、while
D、even if
答案D
解析 此题考查状语从句的引导词。从上下文可以看出，这里应该是一个让步状语从句，而并非时间或者条件状语从句。因此，D项even if符合题意。
转载请注明原文地址:https://jikaoti.com/ti/dhHMFFFM
0

专业英语四级

相关试题推荐
随机试题
最新回复(0)