首页
登录
职称英语
Why don’ t birds get lost on their long flights from one place to another? S
Why don’ t birds get lost on their long flights from one place to another? S
游客
2024-07-23
12
管理
问题
Why don’ t birds get lost on their long flights from one place to another? Scientists have puzzled over this question for a long time. Now they’ re starting to fill in the blanks.
Not long ago, experiments showed that birds use the sun to guide them during daylight hours. How do birds fly at night? Tests with artificial stars have proved that certain night-flying birds are able to follow the stars in their long-distance flights.
A dove had spent its lifetime in a cage and had never flown under a natural sky. But it had an inborn ability to use the stars for guidance. The bird’s cage was placed under an artificial star-filled sky. The bird tried to fly in the same direction as that taken by his outdoor cousins. Any change in the position of the artificial stars caused a change in the direction of his flight.
But the stars are apparently their main means of navigation. When the stars are hidden by clouds, they apparently find their way by such landmarks as river courses, mountain ranges, coast lines. But when it’ s too dark to see these things, the doves circle helplessly, unable to find their way. [br] In total darkness, doves______.
选项
A、use landmarks
B、don’ t know which way to fly
C、fly back home
D、wait for the stars to appear
答案
B
解析
题干意为“在完全黑暗中,鸽子______。”A项“使用地面标志”;B项“找不到正确方向”:C项“飞回家”;D项“等待星星出现”。从最后一段最后一句“But when it’s too dark to see these things,the doves circle helplessly,unable to find their way.”可以选出正确答案为B。
转载请注明原文地址:https://tihaiku.com/zcyy/3689767.html
相关试题推荐
Whydon’tbirdsgetlostontheirlongflightsfromoneplacetoanother?S
Whydon’tbirdsgetlostontheirlongflightsfromoneplacetoanother?S
Whydon’tbirdsgetlostontheirlongflightsfromoneplacetoanother?S
Whydon’tbirdsgetlostontheirlongflightsfromoneplacetoanother?S
Whydon’tbirdsgetlostontheirlongflightsfromoneplacetoanother?S
Whydon’tbirdsgetlostontheirlongflightsfromoneplacetoanother?Sci
Itisa(regret)______thingtomakeanotherpersonsuffer.regretful
All______toHongKongweredelayedbecauseofbadweather.A、flyB、flightsC、fl
Moneymakesmoney.Toputitanotherway,themoreyouinvest,thegreateryour
Qantas(广达斯航空公司)hasmoreflightstomoreplacesthananyotherAustralianair-l
随机试题
[originaltext]Whatdoyouliketodoinyoursparetime?[/originaltext][origin
Doyouevercalllongdistancefromapayphone?Youdialthenumber,an
A.provideB.neverC.whetherD.explanationE.embarrassingF.neither
Scientistshavecuredcolorblindnessinmonkeysusinggenetherapy.As
Mostpeoplewouldagreethat,althoughourageexceedsallpreviousagesin
A.消除传染源 B.切断传播途径 C.保护易感人群 D.开展消毒杀虫 E
下列不属于纤维状绝热材料的是( )。A.岩棉 B.矿绵 C.玻璃棉 D.膨
房地产图不包括()。A.分户图 B.分丘图 C.地形图 D.地籍图
全口义齿基托的唇颊侧边缘应是A:越厚越好,固位力强 B:越薄越好,舒适 C:
2018年1月,孙某、张某、赵某共同出资设立一有限责任公司。孙某以房屋作价出资1
最新回复
(
0
)