题干

课外阅读。

发明家的“老师”

      可以这样说,遍及海、陆、空的千姿百态的生物,都是发明家的“老师”。

从前,有几个船员在北冰洋遇见一条漂浮的小鲸,他们便开船赶去。哪知这条鲸的鳍起了发动机的作用,船员没有追上。船员受此启发,给船装上了“船鳍”,使船航行得更快。后来,又有了仿照鱼类呼吸的原理,制成了“人工鳃”,使潜水员潜入深海。

海豚可以赶超容易船舰或潜艇,这是因为海豚具有流线形体态。它那独特的双层弹性皮肤,成了优良的消振器,能消除湍流的阻力。据试验,用人工仿造的海豚皮做成的鱼雷,航速提高近一倍。

      南极的企鹅平蹒跚而行,但遇到紧急情况,它能以三四千米的时速,在雪地上急驰如飞。原来,企鹅会匍匐在地,蹬起双脚,好像滑雪者。在它的启示下,人们设计出雪地越野汽车。这种无论汽车,用宽阔的底部贴在雪地行驶,时速可达五十千米。

      发明家模仿袋鼠跳跃前进的方法,制成了“跳跃型汽车”。这种新型汽车无需道路,在沼泽、丘陵、草地或沙漠都可通行无阻。

响尾蛇的眼下方有一薄膜,它能在黑夜感知远处动物散发的体温,从而准确地袭击猎物。人们受到响尾蛇的启示,研制出热敏元件,将它装配在导弹里,当作热定位器,就能弹无虚发。

      人们参照蝙蝠在黑夜超声定位的原理,发明了“声纳”,进而制成了盲人探路器。

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    Are you suffering from FOMO—that is, Fear Of Missing Out? Research shows that a growing number of young people are, with worrying reasons for their sleep and schoolwork.

    ____ You aren't able to do your best unless you sleep well. Most experts agree that the optimum(最适宜)number of hours is eight, and this has been accepted as common sense for as long as I can remember. However, I was young once and know most of you get much less sleep than that.

    I read an interesting article in a teachers' magazine recently. ____ Worryingly, the results showed that teenagers are facing a new problem. They may go to bed and get up at appropriate times, but a growing number are waking up in the middle of the night, not to use the bathroom or have a snack, but because of FOMO.

    According to the article, the number of students waking up during the night to check social media is growing. Afraid of missing a comment or opportunity to take part in a chat, teenagers are waking at all times of the night, going online and getting involved. ____

    Experts are worried about this growing trend and the report reveals some worrying statistics: 23% of 12-to 15-year-olds wake up nearly every night to use social media. ____ One in third of the students are constantly tired and unable to function to their full capacity.

    So I'd like to ask you to be responsible when it comes to social media. Switch off your devices at night. The world won't end and your social media will be waiting to greet you in the morning! ____

A. But things are getting out of hand.

B. They did a study of 848 students in Wales.

C. Another 15% wake up at night once a week for the same reason.

D. I give you my word that you won't have missed anything important.

E. All happens when they should be sound asleep.

F. FOMO is the fear that everyone else is having more fun and more excitement than you.

G. Everybody knows how important it is for students to get a good night's sleep every night