网址:http://m.1010jiajiao.com/timu_id_4455333[举报]
Why don’t birds get lost on their long migratory (迁居的) flights? Scientists have puzzled over this question for many years. Now they’re beginning to fill in the blanks.
Not long ago, experiments showed that birds rely on the sun to guide them during daylight hours. But what about birds that fly mainly by night? Tests with artificial stars have proved conclusively that certain night-flying birds are able to follow the stars in their long-distance flights.
One such bird, a warbler(鸣禽) , had spent its lifetime in a cage and had never flown under a natural sky. Yet it showed an inborn ability to use the stars for guidance. The bird’s cage was placed under an artificial star-filled sky at migration time. The bird tried to fly in the same direction as that taken by his outdoor cousins. Any change in the direction of the make-be-live stars caused a change in the direction of his flight. Scientists think that warblers, when flying in daylight, use the sun for guidance. But the stars are apparently their main means of navigation (导航). What do they do when the stars are hidden by clouds? Apparently, they find their way by such landmarks as mountain ranges, coast lines, and river courses. But when it’s too dark to see these, the warblers circle helplessly, unable to get their direction.
【小题1】The reasons why birds don’t get lost on migratory flights__________.
A.have been known to scientists for many years |
B.are known by everyone |
C.have only recently been discovered |
D.will probably remain a mystery |
A.from North America to South America |
B.using what is apparently an inborn navigational ability |
C.only once during their lifetime |
D.when they are freed from their cages |
A.an artificial star | B.some landmarks |
C.their inborn ability | D.A and B |
A.discover workable answers to universal questions by studying particular cases(特别案例) |
B.jump to conclusions |
C.find a law and then investigate(调查) |
D.are disappointed by the habits of animals |
“Fire! Fire!” What terrible words to hear when one wakes up in a strange house in the middle of the night! It was a large, old, wooden house and my room was on the top floor. I jumped out of bed, opened the door and stepped outside the house. There was full of thick smoke.
I began to run, but as I was still only half-awake, instead of going towards the stairs I went in the opposite direction. The smoke grew thicker and I could see fire all around. The floor became hot under my bare feet. I found an open door and ran into a room to get to the window. But before I could reach it, one of my feet caught in something soft and I fell down. The thing I had fallen over felt like a bundle of clothes, and I picked it up to protect my face from the smoke and heat. Just then the floor gave way under me and I crashed to the floor below with pieces of burning wood all around me.
I saw a doorway in fire, then I put the bundle over my face and ran. My feet burned me terrible, but I got through. As I reached the cold air outside, my bundle of clothes gave a thin cry, I nearly dropped it in my surprise. Then I was in a crowd gathered in the street. A woman in a night-dress and a borrowed man’s coat screamed as she saw me and came running madly.
She was the Mayor’s wife, and I had saved her baby.
【小题1】When the fire arose in the middle of the night, the author was _______.
A.at home | B.sleeping | C.sitting in bed | D.both A and B |
A.because he was very brave. | B.because he liked the baby very much. |
C.but he just happened to save it. | D.because it was the Mayor’s baby. |
A.was a stranger there | B.could see nothing |
C.was not completely awake | D.Both A and C |
A.save the baby | B.call for help | C.protect his face | D.run quickly |
A.old and wooden house, a bundle | B.crashed to, fell down |
C.terrible, half-awake | D.bare feet, a borrowed man’s coat |
More people speak English than any other language except Chinese .English is the main language spoken in the United Kingdom,Ireland,Australia,New Zealand,Canada,the United States and some other countries. Altogether more than 450 million people speak English as their everyday language .Another 100 million or more speak at least some English. Most English words come from old Anglo Saxon,French,or Latin words.
Modern English developed through the efforts(努力) of literary(文学的)and political writings .Modern English was influenced by old English,the beginning of the university educated people,Shakespeare,the common language found in the middle of presentday England and an effort to show and standardize(使标准化)English.
British English,known as Standard English or Oxford English,underwent changes during the colonization(殖民)of North America and the creation(创建)of the United States .British English words changed into American English words,such as centre to center,metre to meter,theatre to theater and so on.
Until the 18th century,British and American English were very similar with almost no difference .Immigration(移民) to America by other English peoples changed the language by 1700.Noah Webster,author of the first authoritative(权威的)American English dictionary,created many changes.
【小题1】Modern English developed through______.
A.the efforts of literary writings | B.the efforts of political writings |
C.old Chinese | D.both A and B |
A.British English | B.Standard English | C.Oxford English | D.all of the above |
A.20th | B.19th | C.18th | D.17th |
A.Why more people speak English | B.What modern English is |
C.When British and American English had no difference | D.English and its development |
In the near future, people in some parts of the world will watch a new kind of television. It is called the high definition television or the HD-TV. The main difference between an HD-TV and a normal television is the picture. It is more clear and detailed. This is because the HD-TV has many more points and lines that make a television image. Every color television picture contains thousands of red, green and blue points. They all come together as an image in the eye of the person watching. The points are organized in lines that go across the television screen. There are more than five hundred lines in a normal television. The HD-TV has two times as many. To get this clear picture, you must have a big screen. Experts say people using a small screen will see little difference.
The HD-TV also has clear sound. It is like the sound on a CD. All these improvements make an HD-TV very costly. One kind in Japan now sells for more than twenty thousand dollars .A major problem with the HD-TV is its broadcast signal(传播信号.The signal is bigger than normal because it carries more electronic information.
【小题1】 What is the main difference between an HD-TV and a normal television? It is .
A.the picture | B.the shape | C.the voice | D.the weight |
A.It is made up of thousands of red, green, and blue points. |
B.Points are organized in lines that go across the TV screen. |
C.It is a black and white picture |
D.Both A and B |
A.Over 250 | B.More than 500 |
C.More than 1,000 | D.About 250 |
A. You must have the bigger signal for the HD-TV.
B. You have to get a big screen.
C. You should have a compact disc player.
D. Both A and B. 查看习题详情和答案>>
短文填词 (共10小题,每小题1分,满分10分)
Books are our friends. They introduce us many different kinds of knowledge.
They lead us down the road to __【小题1】___(成功). Books are our teachers. They ___【小题2】___ us truth, science, literature, and philosophy of life; ____【小题3】__ (此外),they increase our knowledge, enlarge our experience, strengthen our character and do many o__【小题4】___ things which we can __【小题5】___ do without them. We have to learn as long as we live. Butour life is ___【小题6】___ (有限的), and the knowledge is boundless. There aremany things __【小题7】___ are very necessary to learn and there are also manywhich should be ___【小题8】__ (回避). Books tell us what is good and what is not. And only books can tell the good __【小题9】___ the bad. Therefore, to read more books is the b_【小题10】___ policy for us young students.