三天过去了,也没有使蚊子减少。 面对成群的蚊子,大家感到束手无策。野牛提议说:“我去请居住在石洞里的蝙蝠吧,也许它们能够消灭夜间飞舞的蚊子。” 孔雀听了说:“请那些黑不溜秋、模样古怪的.蝙蝠来灭蚊,它们能行吗?” 羚羊听了说:“蝙蝠眼睛高度近视,夜间难道能看见蚊子吗?” 野牛说:“你俩别先下结论,我去把蝙蝠请来试试不就知道啦!” 狮子大王说:“野牛,你快去请吧!” 野牛把蝙蝠家族请来了。它们成群地从山洞里飞出来,选择在蚊子出来活动的傍晚和清晨进行捕。在昏暗的低空里,蝙蝠们依靠发出的声音,用超声波定位认准目标,飞上飞下,时隐时现,追捕蚊子准确无误。
三天后,森林里的蚊子果然少了很多。狮子大王高兴地对蝙蝠家族说:“你们灭蚊有功,‘灭蚊冠军’的称号非你们莫属!” 孔雀和羚羊知道蝙蝠获奖,自觉羞愧。 寓意:对待任何事物都需要去了解情况。而不是武断地下结论。
今天,在老师的带领下我们学习了《蝙蝠和雷达》这篇课文。
这篇课文的主要内容是讲科学家从蝙蝠身上得到启示,经过多次试验研究,由此发明了雷达。你也许会问吧:蝙蝠和雷达可以说是“八竽子打不着”,它们怎么会有牵连呢?好了,我来告诉你吧,你在电视里或许看到过一些蝙蝠在夜晚飞出洞穴去寻找食物吧,可你见过它们碰到障碍物上吗?
没有吧,你知道这是怎么回事吗?原来,蝙蝠有一套可以在夜间安全飞行的“秘密武器”使它不会与障碍物相撞。科学家经过试验得知了这个答案,而且发现,蝙蝠夜间飞行并不是靠眼睛,而是靠它们的嘴巴和耳朵配合指挥路的。因为蝙蝠的嘴巴可以发出一种人类听不到的声音,叫超声波。这种超声波像波浪一样推到前方,超声波遇到障碍物又传回蝙蝠的耳朵里,蝙蝠便得知前方有障碍物,并绕道而行。所以蝙蝠能安全地在夜空飞行。 三眼看世界
从这篇课文中我明白了,大自然的'力量真伟大,它就像人类的好老师一样,无时无刻不在给我们启示。
星期六,我读了《蝙蝠和雷达》这篇文章,我的感受非常深。飞机在漆黑的夜里飞行,人们不能保证飞机是否安全,所以很担忧。但是人们知道蝙蝠也是在夜间飞行的,而且蝙蝠能很快地捕捉飞蛾和蚊子,还不会与其它东西相撞。为了弄清楚蝙蝠为什么在夜间飞行时不会受到任何伤害,科学家一共做了三次试验。第一次是把蝙蝠的眼睛蒙上,蝙蝠依然能自由飞行;后两次是把鼻子和嘴巴塞住,结果它飞行时磕磕撞撞。科学家才知道,原来蝙蝠是靠耳朵来飞行的。
科学家经过研究,知道蝙蝠的嘴里能发出一种超声波,人是听不见的,蝙蝠能听见。蝙蝠就靠它来飞行。科学家从中得到启发,给飞机装上雷达,解决了飞机在夜间安全飞行的问题。其实,在我们生活中都可以发现一些科学道理。就像苹果从树上掉下来,牛顿因此发现了万有引力;人们受鸟儿飞行的启发,发明了飞机。人类在大自然中生存,如果善于思考,善于观察,就会从大自然中得到帮助。大自然永远是人类的老师。从现在起,我要认真学习知识,长大要做一个伟大的科学家,从大自然里研究出更多有关的成果。
从前,有个人种了一棵葫芦。细长的葫芦藤上长满了绿叶,开出了几朵雪白的小花。花谢以后,藤上挂了几个小葫芦。多么可爱的小葫芦哇!那个人每天都要去看几次。
有一天,他看见叶子上爬着一些蚜虫,心里想,有几个虫子怕什么!他盯着小葫芦自言自语地说:“我的小葫芦,快长啊,快长啊!长得赛过大南瓜才好呢!”
一个邻居看见了,对他说:“你别光盯着葫芦了,叶子上生了蚜虫,快治一治吧!”那个人感到很奇怪,他说:“什么?叶子上的虫还用治?我要的是葫芦。”
没过几天,叶子上的蚜虫更多了。小葫芦慢慢地变黄了,一个一个都落了。
一天晚上,蝙蝠飞出来找吃的。突然发现了一架飞机在空中飞翔,非常奇怪。一番侦察后,得知原来是雷达帮助了飞机。它是如何帮助飞机在夜里安全飞行的呢?蝙蝠决定去拜访雷达。蝙蝠有礼貌地说:“兄弟,请问尊姓大名?”“你好,我叫雷达”,雷达说。“你怎么能跟我一样,在空中飞呢”?蝙蝠有了疑问。雷达说“是伟大的科学家从你身上得到了启发,发明了我。”蝙蝠说:“那飞机是怎么工作的呢?”“飞机发出的无线电波就像你的超声波,飞机的荧光屏就像是你的耳朵”,雷达告诉蝙蝠。“哦!原来是这样啊,科学家们真伟大啊”,雷达恍然大悟。蝙蝠说:“再见了,老兄。”雷达说:“886!”
今天,我读了《蝙蝠与雷达》,这篇文章主要讲了:科学家模仿蝙蝠探路的方法,给飞机装上了雷达。雷达通过天线发出无线电波,无线电波遇到障碍物就反弹回来,显示在荧光屏上。驾驶员从雷达的荧光屏上,能够看清楚前方有没有障碍物,所以飞机在夜里飞行也十分安全。
读完这篇文章我懂得了:自然界中生物的本领,常常引起人们浓厚的兴趣。比如,青蛙的眼睛非常奇怪,它们看活动的东西很敏锐,可是对静止的东西却“视而不见”,人们的指挥人员在“电子蛙眼”的帮助下,能更加准确指挥飞机的降落。人们研究生物某些器官的构造和功能,从中得到启示并进行模仿,研制成功新的仪器、机械,于是产生了一种科学,就是仿生学。
模仿例句写句子
一、Model1:Who’sshe?She’smygrandmother.
1._____________________________________________________(he,grandfather
2.____________________________________________________(they,myfriends
Model2:She’smygrandmother.
1._______________________________________________(he’s,grandfather
2._______________________________________________(they’re,friends
二、Model:Areyoutall?Yes,Iam.
1._____________________________________________________(thirsty,yes
2._____________________________________________________(short,no
三、Model1:CanIhaveapeach?
1.________________________________________________(useyourbook
2._______________________________________________(borrowyourrulerModel2:CanIgotothezoo?
1.____________________________________________________(watchTV
四、Model1:WhatdoyoudoonTuesday?Iplaybaseball.
1.____________________________________________________(Tuesday,playthepiano
2.____________________________________________________
(Saturday,playbasketball
Model2:DoyouplaysocceronTuesday?
1.__________________________________________________(they,Friday
2.__________________________________________________(she,MondayModel3:IplaytheviolinonMonday.
1._____________________________________________________(playping-pong
Model4:DoyouplaybaseballonTuesday?Yes,Ido.
1._____________________________________________________(playsoccer,Friday
2._____________________________________________________(playtheviolin,Thursday
Model5:WhatdoyoudoonThurday?
1.____________________________________________________(Wednesday
2._____________________
________________________________(Tuesday
Model6:IplaybaseballonFriday.
1._________________________________________________________(playping-pong,Monday
2.________________________________________________________(playthepiano,Sunday
Model7:IwatchTVonFriday.
1.________________________________________________________(gotothezoo,Sunday
2.________________________________________________________(playtheviolin,Tuesday
五、Model1:Whatdayisittoday?It’sMonday.
1.______________________________________________________
(Thursday
2.______________________________________________________
(Wednesday
六、Model1:Iwantacomputer.
1.____________________________________________________(they,toycar
2._____________________________________________________(he,guitarModel2:Whatdoyouwant?Iwantadrum.
1.__________________________________________________
(they,toycar
2.__________________________________________________
(she,skateboard
3.__________________________________________________
(Lisa,drum
Model3:Doyouwantadoll?
1.___________________________________________________(they,puzzle
2._________________________________________________(she,skateboardModel4:Doeshewantadoll?
1.______________________________________________________(she,puzzle
2.______________________________________________(Tony,stuffedanimalModel5:Doyouwantadrum?No,Idon’t.
1._____________________________________________________(she
七、Model1:It’sonthesofa.
1.__________________________________________________
(drum,nexttothesofa
2._________________________________________________
(socks,behindthebookcase
Model2:Mywalletisonthechair.
1._________________________________________________
(drum,nexttothesofa
2._____________________________________________
(socks,infrontofthebookcase
Model3:Theyareinfrontofthebookcase.
1._____________________________________________________(nextto
2._____________________________________________________(behind
八、Model1:Ilikeart.
1.______________________________________________(English
2.______________________________________________(history,scienceModel2:Ilikeartandmath.
1.__________________________________________________(English,history
2.__________________________________________________(science,P.E.Model3:Ilikescience.
1.___________________________________________________(they,history
2.___________________________________________________(we,English
九、Model1:Where’smywallet?
1.__________________________________________________(computergame
2.__________________________________________________(stuffedanimal
3.____________________________________________________(books
十、Model1:What’sshedoing?She’spainting.
1.______________________________________________________
(he,running
2.______________________________________________________
(it,sleeping
3.______________________________________________________
(Tony,playing
4.______________________________________________________
(they,running
Model2:Whatareyoudoing?Iameating.
1._____________________________________________________
(they,sleeping
2._____________________________________________________
(she,shopping
3.____________________________________________________
(yourparents,eating
Model3:Whatareyoudoing?I’mwriting.
1.____________________________________________________(run
Model4:Whatisshedoing?Sheisplaying.
1.________________________________________________________(he,study
2.________________________________________________________(they,write
十一、Model1:Touchyournose.
1._________________________________________________(close,eyes
2.__________________________________________________(open,mouthModel2:Touchyoureyes.
1.___________________________________________________(hands
2.___________________________________________________(feet
Model3:Touchyournose.
1.___________________________________________________(her,arms
2.___________________________________________________(his,feetModel4:Closeyourmouth.
1.___________________________________________________(herbooks
2.___________________________________________________(hiseyes十二、Model1:Whosecarisit?It’smine.
1.______________________________________________________
(dog,hers
2.______________________________________________________
(stuffedtoy,Jenny’s
Model2:Whoseskateboardisthis?It’smine.
1.____________________________________________________
(boat,hers
2.____________________________________________________
(computergame,theirs
Model3:Whosecarisit?It’shers.
1.____________________________________________________
(bag,his
2.____________________________________________________
(boat,ours
Model4:Whosepuzzleisthis?It’shers.
1._____________________________________________________
(toycar,mine
Model5:Whoseballoonisthis?It’smine.
1.________________________________________________________(puzzle,hers
2.________________________________________________________(suffedtoy,Jenny’s
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