首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
A、To clear up the eggs of insects. B、To help trees deliver water. C、To look for the signs of insects. D、To prepare for cutting d
A、To clear up the eggs of insects. B、To help trees deliver water. C、To look for the signs of insects. D、To prepare for cutting d
admin
2018-06-27
70
问题
A beetle invasion in the United States has killed at least twenty million ash trees. The invasion of the emerald ash borer was first discovered near Detroit, Michigan, in 2002. Experts believe the small green insects arrived in the 1990’s in shipments of goods from China.
[16] The emerald ash borer has destroyed trees in the Midwest and as far East in the United States as Maryland. [17] The insects have also spread as far north as Ontario, Canada.
Ash trees can resist many diseases. But they cannot resist the emerald ash borer. [18-1] It lays eggs on the bark.The young larva drill into and feed on the inner bark. This harms the ability of the tree to transport water and nutrition.
In some places, farmers are using “detection trees”. They have an area where bark has been cut away. The area circles the tree. [18-2] The process weakens the tree. It makes them easier targets for borers, and shows if the insects are nearby.
Efforts to stop the spread of the emerald ash borer include cutting down affected trees. There are worries that the ash tree might disappear unless the invasion is controlled. To prepare for such a possibility, a government laboratory is asking people to send in the seeds from ash trees. [19] It examines and X-rays the seeds to make sure there are no living borer fertilized eggs.Only the best seeds are remained and then sent for storage in a seed bank. There, they are dried and frozen. Should the seeds ever be needed, the hope is that scientists might someday develop an ash tree that could resist the little green attackers.
1.What’s the speaker mainly talking about?
2.How far do the insects spread northward?
3.Why is part of the bark cut away?
4.What is the government laboratory trying to do?
选项
A、To clear up the eggs of insects.
B、To help trees deliver water.
C、To look for the signs of insects.
D、To prepare for cutting down trees.
答案
C
解析
转载请注明原文地址:https://kaotiyun.com/show/uKT7777K
0
大学英语六级
相关试题推荐
A、Brighterpeoplegotbetterpay.B、Payscaleswerenotfairatall.C、Maleswerebrighterthanfemales.D、Paysdependedonone’
今天,剪纸(paper-cutting)和古代一样是一项技术性很高的艺术形式,它需要创造力、技巧和经验。无论是简单的还是复杂的形式,每一个设计必须形成一个连续的、完整的(integral)剪纸。仔细研究你会发现中国人形成的那种巧妙的剪法既连接了内部的各个部
A、Specialeducation.B、Biomedicalengineering.C、Artificialintelligence.D、Imagingsystem.B本题问的是在工作需求量方面,哪一个领域将会增长最快。短文中指出,在未来
A、Costly.B、Time-consuming.C、Genuine.D、Safe.B讲座中提到,随着互联网改革每日都带来新型的沟通方式,建立联系不再是一项麻烦的、耗时的事情。
A、Salary.B、Holiday.C、Workingcondition.D、MedicalbenefitsiD本题问的是什么在女性定义职业成功中非常重要。短文中提到根据调查女性称医疗福利是定义职业成功的一个重要部分。
A、Theywillbuysomethingfromtheconveniencestores.B、Theywilltakeadvantageofthetimetorestawhile.C、Theywillhave
A、Improvedairconditionandbetterhealth.B、Reducedtrafficcostsandthegreaterfitness.C、Lessinfrastructuredemandsandc
A、HewasoneofthegreatestemperorsinHanDynasty.B、HebroughttoPersiaanewbreedofhorsefromChina.C、Hewasconsidere
It’sperhapstheworld’smostfamousunderwaterattraction,immortalizedinfilmandinlegend:theTitanic.Butnowexpertssay
随机试题
Ithinkthatwhatitisnotthattheworldhasbecomecrueler,it’sjustthatweholdourchildrenbackfromaveryearlyage.W
We______ourbreakfastwhenanoldmancametothedoor.
患者,女,51岁,平素头晕头痛,耳鸣目眩,少寐多梦,突然发生口眼歪斜,舌强语謇,半身不遂,舌质红脉弦细数。治疗方剂宜选
A.50ml/kgB.60~80ml/kgC.70~100ml/kgD.100一120ml/kgE.120~150ml/kg中度脱水第一天补液量
[2016真题·单选(选做)]集线器是对网络进行集中管理的重要工具,是各分枝的汇集点。集线器选用时要注意接口类型,与双绞线连接时需要具有的接口类型为()。
应逐个进行壳体压力试验和密封试验的阀门是()。
关于投资性房地产有关的支出,下列说法中正确的有()。
2013年,全球汽车零部件贸易涉及237个国家和地区,反映了汽车工业空间分布更分散,全球化程度更高,区域分工逐渐深化,回答下列问题。对汽车零部件的贸易比整车贸易更活跃的原因分析不正确的是()。
由左侧展开图折成的立方体是:
Whatdoesthewomanmean?
最新回复
(
0
)