9.Coral reefs(珊 瑚 礁)are not just beautiful to look at,but also very useful.They shelter nearly 25% of ocean life and provide food for billions of people.However,like many other species,this amazing ecosystem(生态系统)is in danger of dying out!
There are two main reasons for the destruction-the rising carbon dioxide levels caused by global vdarming as well as human influences like bottom operation.hile not much can be done about the former,the loss caused by the latter can be reduced.
Bottom operation involves dropping nets to the ocean bed and then dragging them up when filled with fish.This action damaged te ocean floor,causing the coral branches to separate from the reefs.While that is very discouraging,the good news is that if these branches are found quickly,they can be saved.At present,that work is being performed by volunteer divers.But the method has only limited sccess because they cannot stay long underwater,nor reach depths of over 200meters where some of the deep-sea coral grows.
However,this is not the case for Coralbots-mthe robots that can constantly seek out broken branches.A team of‘coralbots',each individually working to simple rulesl will piece together'damaged bits of coral,allowing them to regrow.They are programmed to be able to distinguish between other things and the coral.The robots work together in groups,similar to bees.If one coralbot is damaged then the others will still be able to complete the task.
Dr Lea-Anne Henry said:"The project of using coralbots offers us the possibility to restore(修复)the function of reefs.It is in the final stage of testing.Once ready,the researchers hpe to build hundreds of them and use them effectively in the waters off Scotland and then hopefully in the oceans across the world."
24.Which of the following is a cause of the danger that coral reefs are facing?D
A.The appearance of new creatures.
B.The seriously polluted sea water.
C.The activities of volunteer divers.
D.Human activities like bottom operation.
25.Compared with volunteer divers,coralbotsA.
A.can stay longer underwater B.must work as bees do
C.can distinguish what is coral D.can never be damaged
26.What does the underlined word"them"in the last paragraph refer to?A
A.Coralbots. B.Broken branches.
C.working bees. D.Bits of coral.
27.We can infer from the passage thatB.
A.bottom operation has affected most underwater creatures
B.broken branches of coral can regrow if saved in time
C.hundreds of the coralbots have worked well in the oceans
D.with the coralbots all damaged coral reefs can be restored.
分析 本文主要讲述了珊瑚礁所面临的问题以及应对的方法.珊瑚礁由于全球变暖以及人类的影响而面临着灭绝的危险.潜水员不能长时间的待在水里对珊瑚礁进行修复,但是Coralbots,它们可以不断地寻找断枝,帮助受损的珊瑚礁重新生长.
解答 24.D 细节理解题.由第二段There are two main reasons for the destruction-the rising carbon dioxide levels caused by global warming as well as human influences like bottom operation.可知有两个原因导致珊瑚礁面临灭绝,一个是全球变暖,另一个是人类影响像海底操作,故选D.
25.A 细节理解题.由第三段But the method has only limited success because they cannot stay long underwater,nor reach depths of over 200 meters where some of the deep-sea coral grows.可知志愿者不能长时间呆在水下;由第四段However,this is not the case for Coralbots-mthe robots that can constantly seek out broken branches可知Coralbots可以长时间呆在水下,故选A.
26.A 词语辨析题.由最后一段 use them effectively in the waters off Scotland and then hopefully in the oceans across the world.可知这里的them指代的是上文提到的Coralbots,故选A.
27.B 推理判断题.由第三段the good news is that if these branches are found quickly,they can be saved.可知珊瑚礁的分支如果被及时发现,就可以重新生长,故选B.
点评 本文考察学生的理解推断能力以及细心程度,只要抓住文章的关键词,采用寻读的方法查找细节,就能找到正确答案.