精品一区二区免费在线观看_国产精品久久久久久av福利软件_97成人精品区在线播放_国内成人精品一区

Why would an animal kill itself? It seems a strange question, and yet it is one that has made some scientists curious for a long time. For there is a kind of animal called lemming（旅鼠）, that periodically killed themselves together, and no one knows just why!

The small creatures which live in the Scandinavian mountains, feed on a diet of roots and special insects and live in nests they dig underground. When their food supply is large, the lemmings live a normal and undisturbed life. 

However, when the lemmings’ food supply becomes too low to support the population, a singular migration（遷徙）begins. The lemmings leave their nests in groups. Great numbers of them begin to travel across the Scandinavian plains, a journey that may last weeks. The lemmings eat everything in their path, continuing their long march until they reach the sea. 

The reason for what follows remains unbelievable to naturalists. Upon reaching the coast, the lemmings do not stop but swim by the thousands into the sea. Most stay afloat only a short time before they tire, sink and drown. 

A common theory for this mass self-killing is that the lemmings do not realize that the ocean is such a huge body of water in their cross-country journey, the animals must cross many smaller bodies of water, such as rivers and small lakes. They may think that the sea is just another such swimmable path to go through. But no final answer has been found to the strange happening. 

1.The passage is mainly about______. 

A. how lemmings find food

B. why animals kill themselves

C. the lemmings’ self-killing

D. the food supply in the Scandinavian mountains

2.A reason for the lemmings’ self-killing might be that they______. 

A. go mad from a lack of food

B. hope to find fish for food

C. decide to reduce the population

D. think they can cross the sea

3.Why are scientists curious about the lemmings’ behavior?

A. Because they are the only animals that live in Scandinavia.

B. Because it is very unusual for animals to kill themselves.

C. Because of the amount of food they can eat on their march to the sea.

D. Because they can gather together in such huge numbers.

4.The underlined word “singular” means______.

A. unusual       B. single       C. wonderful      D. common

 

閱讀下面短文，掌握其大意，然后從各題所給的四個選項（A、B、C和D）中，選出最佳選項，并在答題卡上將該項涂黑。

When I come across a good article in reading newspapers，I often want to cut and keep it．But just as I am about to do so，I find the article on the   21   side is much interesting．It may be a discussion of the way to   22   in good health，or advice about how to behave and   23    yourself in society．If I cut the front articles，the opposite one is likely to suffer   24   ，leaving one half of it or keeping the text    25    the title．Therefore，the scissors would stay before they start，    26   the cutting would be halfway done when I find out the   27    result．

Sometimes two things are to be done at the same time，both worth your   28    ．You can only take up one of them；the other has to wait or be   29   up．But you know the future is unpredictable—the changed situation may not   30   you to do what is left behind．Thus you are   31    in a difficult position and feel sad．How come nice    32  and clever ideas should gather around all at once? It may happen that your life   33   greatly on your preference of your one choice to the other．

In fact that is what   34   is like；we are often   35   with the two opposite sides of a thing which are both  36    like a newspaper cutting．It often occurs that our attention is   37   to the thing only after we get into another．The former may be more important than the latter and this   38  _ a divided mind．I still remember a philosopher’s   39  ：“When one door shuts，another opens in life．”So a casual（不經意的）    40    may reward one．

A．same          B．opposite        C．either         D．front

A．get        B．bring        C．1ead          D．keep

A．enjoy         B．help          C．conduct        D．dress

A．damage       B．destroy          C．hurt           D．injury

A．on          B．for            C．without         D．off

A．or           B．but            C．so             D．for

A．satisfying     B．regrettable      C．surprising      D．impossible

A．courage      B．patience         C．strength         D．attention

A．given          B．picked       C．held          D．made

A．persuade   B．agree          C．allow          D．tell

A．filled        B．struck         C．caught          D．attracted

A．chances     B．conditions      C．wishes          D．ways

A．progresses  B．goes          C．changes         D．improves

A．study        B．1ife           C．society              D．nature

A．supplied   B．connected       C．fixed        D．faced

A．available   B．desirable       C．considerable   D．enjoyable

A．turned      B．transferred     C．paid           D．drawn

A．gives way toB．gives rise to   C．gets through to D．gets close to

A．remarks    B．sayings         C．slogans          D．comments

A．behavior     B．action          C．choice       D．attitude

根據短文內容，從短文后的選項中選出能填入空白處的最佳選項。選項中有兩項為多余選項。

Sometimes we are asked to make a speech in life, but most of us don’t do a very good job.  1

So, you have to give a speech — and you are terrified. You get nervous, you forget what you want to say, you stumble (結結巴巴) over words, you talk too long, and you bore your audience. Later you think, Thank Goodness, it’s over. I’m just not good at public speaking. I hope I never have to do that again.

Cheep up!  2  Here are some simple steps to take the pain out of speech making. Ask yourself the purpose of your speech. What is the occasion? Why are you speaking? Then, gather as many facts as you can on your subject. Spend plenty of your time doing your research. Then spend plenty of your time organizing your materials so that your speech is clear and easy to follow. Use as many examples as possible, and use pictures, charts, and graphs if they can help you make your points clearer. 3  Don’t talk over their heads, and don’t talk down to them. Treat your audience with respect. They will appreciate your thoughtfulness.

Just remember: Be prepared. Know your subject, your audience, and the occasion. Be brief.  4  And be yourself. Let your personality come through so that you make person-to-person contact with your audience.

If you follow these simple steps, you will see that you don’t have to be afraid of public speaking. In fact, you may find the experience so enjoyable that you volunteer to make more speeches! You’re not convinced yet? 5

A. It doesn’t have to be that bad.

B. Take several deep breaths after your speech.

C. This article gives some advice on how to give a good speech.

D. Say what you have to say and then stop.

E. Don’t say what you aren’t familiar with.

F. Never forget your audience.

G. Give it a try and see what happens.

完形填空。閱讀下面短文，從短文后各題所給的四個選項（A、B、C、D）中，選出可以填入空白處的最佳選項，并在答題卡上將該項涂黑。

One of my father’s favorite sayings as I was growing up was “Try it!” I couldn’t say I didn’t like 21, whatever it might be, 22 I tried it. Over the years I’ve come to 23 how much of my success I owe to my 24 of those words as one of my values. My 25 job was just one I decided to try for a couple of years until I 26 what I wanted to do as a career (職業) .  27 I believed I would work for a few years, get married, stay home and raise a family, so I didn’t think the job I took 28 that much . I couldn’t have been more 29. I mastered the skills of that beginning level position and I was given the opportunity (機會) to 30 through the company into different 31. I adopted each new opportunity with the 32, “Well, I’ll try it; if I don’t like it I can always go back to my 33 position.” But I was with the same company for the past 28 years , and I’ve 34 every career change I’ve made. I’ve discovered I 35 a large number of different talents (才能) and skills that I never would have thought were within me had it not been for my being 36 trying new opportunities. I’ve also discovered that if I 37 what I’m doing and word hard at achieving my 38. I will succeed. That’s why I am so 39 to be a part of CareerFables.com. I think 40 has come and I am determined to make it a success.

21. A. everything     B. something   C. everybody    D. somebody

22. A. until after      B. ever since   C. so that       D. long before科23. A. consider      B. argue        C. include      D. realize

24. A. suggestion    B. explanation   C. acceptance     D. discussion學科25. A. hard         B. best         C. extra         D. first

26. A. determined    B. examined   C. experienced    D. introduced

27 A.  Actually     B. Gradually     C. Finally       D. Usually

28. A. helped       B. required      C. expressed      D. mattered

29. A. careful      B. mistaken      C. interested      D. prepared

30. A. look up      B. take up       C. move up       D. put up

31. A. situations    B. choices       C.  directions     D. positions學網

32. A. thought     B.  reply        C. action         D.  advice

33. A. easier      B.  newer        C.  earlier        D.  higher

34. A. permitted    B. counted      C. organized      D. enjoyed

35. A. show       B. possess       C. need         D. gather

36. A. lucky for    B. slow at       C. open to       D. afraid of

37. A. think of     B. give away     C. believe in     D. turn into

38. A. business    B. goal         C. fortune       D. growth

39. A. excited     B. curious       C. surprised     D. helpful

40. A. dream      B. time         C. power       D. honor

Astronomers have captured(捕獲) the first direct image of a planet being born.

Adam Kraus, of the University of Hawaii’s Institute for Astronomy, said the planet is being formed out of dust and gas circling a 2-million-yea-old star about 450 light years from Earth.

The planet itself, based on scientific models of how planets form, is believed to have started taking shape about 50,000 to 100,000 years ago.

Called LkCa 15b, it’s the youngest planet ever observed. The previous record holder was about five times older.

Kraus and his colleague, Michael Ireland from Macquarie University and the Australian Astronomical Observatory, used Keck telescopes on Mauna Kea(a volcano on the island of Hawaii, US) to find the planet. Kraus presented the discovery Wednesday at NASA’s Goddard Space Flight Center in Maryland.

Observing planets while they’re forming can help scientists answer questions like weather planets form early in the life of a star or later, and whether they form relatively close to stars or father away.

Planets can change orbits(軌道) after forming, so it’s difficult to answer such questions by studying older planets.

“These very basic questions of when and where are best answered when you can actually see the planet forming, as the process is happening right now,” Kraus said.

Scientists hadn’t been able to see such young planets before because the stars they’re circling around outshine(光亮強過) them. Kraus and Ireland used two techniques to overcome this problem.

One method, which is also used by other astronomers, was to change the shape of the telescope mirrors to remove light distortion(扭曲) created by the Earth’s atmosphere. The other method they used, which was unique, was to put masks with several holes over most of the telescope mirrors. The combination of these techniques allowed the astronomers to obtain high-quality images that let them see the planet next to the bright star.

The star LkCa 15—the planet is named after its star—was the team’s second target. They immediately knew they were seeing something new, so they plan to gather more data on the star.

1.The research on younger planets helps scientists _____________.

A. study why planets change orbits after forming

B. understand how planets move around their stars

C. answer questions about the age of stars and planets

D. know the relationship between planets and their stars

2.Why are young planets like LkCa 15b hard to discover?

A. Their stars are brighter than them..      B. They are very far from the earth.

C. They are generally too small.           D. They rarely form.

3.According to the text, Kraus and Ireland _____________.

A. have been working in the same university

B. observed the planet on a volcano in Hawaii

C. used two new methods in the observation

D. cut holes in the mirrors when observing

4.Which of the following would be the best title for the text?

A. Youngest planet seen as it’s forming.

B. Planet 450 light years away discovered.

C. World’s first direct image of a planet taken.

D. New technique helps discover young planets.