首页
登录
职称英语
[originaltext] Scientists have observed that [19]plants themselves produce m
[originaltext] Scientists have observed that [19]plants themselves produce m
游客
2024-01-31
60
管理
问题
Scientists have observed that [19]plants themselves produce many poisonous chemicals for defense against insects. But insects have developed ways of dealing with them and, in fact, have been eating plants for about 250 million years. Now insects are using these same mechanisms to deal with man-made poisons—insecticide. This is why resistance of insects to insecticide has developed so rapidly. What should be done? [20]Scientists studying the problem suggest that farmers use less insecticide. At the moment, farmers regularly spray crops as a precaution against problems that are caused by large numbers of pests. They should, instead, spray only where pests have actually been seen. Secondly, farmers could use a combination of two or three insecticide at once. To survive, the insects would need to become resistant to two or more poisons at the same time. [21]The most surprising suggestion, perhaps, is that, at certain times of the year, farmers should actually try to attract new insects onto the crops they are trying to protect. The new insects will mate with those which survived from a certain kind of insecticide and will lessen the latter’s resistance to it.
Scientists hope that these and other measures will postpone the day when farmers and scientists will have to stand by while new super bugs which may be resistant to all our poisons invade our farms and devour our crops.
19. What does the speaker say about plants?
20. What is mentioned as one of the suggestions raised by scientists?
21. What is the most surprising suggestion scientists give?
选项
A、Using less insecticide.
B、Giving the plants up.
C、Spraying crops frequently.
D、Trying other insecticide.
答案
A
解析
短文提到了科学家给农场主的三点建议:少用杀虫剂、同时使用两种或三种杀虫剂、吸引别的昆虫到田间。A正是短文中提及的建议之一,故为答案。
转载请注明原文地址:http://tihaiku.com/zcyy/3409858.html
相关试题推荐
[originaltext]Wearerapidlynearingtheendofthiscourseinthehistory
[originaltext]Wearerapidlynearingtheendofthiscourseinthehistory
[originaltext]Thediamondisconsideredthemostfamousandvaluablejewel
[originaltext]Thediamondisconsideredthemostfamousandvaluablejewel
[originaltext]EverycountryintheworldcelebratesNewYear,butnotevery
[originaltext]EverycountryintheworldcelebratesNewYear,butnotevery
[originaltext]W:Oh,Steve,you’reearly!I’mhappyyou’rehereearlytodaybec
[originaltext]W:Dr.Carter’sOffice.M:Yes,I’dliketomakeanappointmentt
[originaltext]W:Dr.Carter’sOffice.M:Yes,I’dliketomakeanappointmentt
[originaltext]"AlargefirebrokeoutTuesdayinEgypt’sparliamentandfiv
随机试题
DictationListentothepassage.Forquestions21—25,fillintheblankswithth
Duringanaverageyear,about50peoplediefromcarbonmonoxidepoisoningin
【B1】[br]【B12】A、appreciateB、apologizeC、approveD、accountD此句的意思是“网络的使用使人们减少了和
Thepointoffactoryfarmingischeapmeat,madepossiblebyconfininglarge
[originaltext]Peoplewhoaremarriedorincommittedrelationshipsareheal
2014年6月15E1至25日,在卡塔尔首都举行的第38届世界遗产大会上,我国
根据《中华人民共和国慈善法》,慈善信托的受托人应当根据信托文件和委托人的要求,及
患者,女,41岁,近3年月经常有淋漓量多,曾大出血两次。近两个月来因劳累过度又见
根据《行政诉讼法》和有关司法解释的规定,下列关于行政诉讼证据和举证的说法中,正确
支架法施工时应考虑施工预拱度,下列不属于施工预拱度的是( )。A.支架在荷载作
最新回复
(
0
)