【题目】You have probably heard of homing pigeons, which usually appeared in wars. From 3000 B. C. to the present, homing pigeons have 【1】 as postmen. They have been especially useful for carrying messages 【2】 wars. The telegraph is not 【3】 to carry about. Sometimes only the little pigeon can take a message where it ought to go.

In 1870,when the Prussians surrounded the city of Paris, the city was cut off from all the 【4】 means of communication. The people 【5】 many different ways of sending news. One way was to let go small balloons carrying mail. 【6】 of course, they only drifted ( 【7】 the wind carried them. Often they landed inside the enemy's lines. Even balloons large enough to carry a pilot could hardly be 【8】 controlled.

It was pigeons that in the end solved the 【9】 . Homing pigeons were brought into the city. Soon they were carrying letters far and wide. The enemy brought 【10】 to catch pigeons, but the little postmen could fly faster than their 【11】 Strangely enough, pigeons played an important 【12】 during the war.

During the First World War every army unit had a group of pigeons 【13】 . Many of them were 【14】 . Among them was an American pigeon with a French name Cher A mi, which meant " dear friend". A group of US soldiers were surrounded by the enemy. They had no food and no bullets. They nearly died of 【15】 . There was little hope for them. Cher Ami made his way 【16】 the bullets and succeeded. At once planes 【17】 to drop food and ammunition(军火)to them. With their strength 【18】the soldiers fought back to their own army and eot saved.

【19】 can pigeons carry the message? There were various methods. Usually the message is put into a little glass tube. The tube is tied to the leg or hidden under 【20】 or hung around the neck.

A. considered B. served C. regarded D. made

A. in favour of B. in need of C. during D. in time of

A. easy B. difficult C. necessary D. important

A. present B. past C. usual D. ordinary

A. used B. did C. tried D. managed

A. And B. Though C. Since D. But

A. which B. that C. to which D. where

A. well B. rather C. only D. just

A. questions B. situation C. problem D. thing

A. dogs B. soldiers C. planes D. hawks

A. enemies B. postmen C. balloons D. bullets

A. action B. part C. ball D. game

A. trained B. taught C. bought D. fed

A. killed B. sold C. honoured D. sent

A. the enemy B. hunger C. anger D. war

A. for B. to C. in D. through

A. landed B. found out C. set out D. set about

A. recovered B. arrived C. lost D. missing

A. Why B. How C. When D. Where

A. the head B. the body C. the foot D. a wing

【题目】Even plant can run a fever, especially when they're under attack by insects or disease. But unlike human, plants can have their temperature taken from 3,000 feet away straight up. A decade ago, adopting the infrared (红外线)scanning technology developed for military purposes and other satellites, physicist Stephen Paley came up with a quick way to take the temperature of crops to determine which ones are under stress. The goal was to let farmers precisely target pesticide (杀虫剂)spraying rather than rain poison on a whole field, which invariably includes plants that don't have pest(害虫)problems.

Even better, Foley's Remote Scanning Services Company could detect crop problems before they became visible to the eyes. Mounted on a plane flown at 3,000 feet at night, an infrared scanner measured the heat emitted by crops. The data were transformed into a color-coded map showing where plants were running " fevers". Farmers could then spot-spray, using 50 to 70 percent less pesticide than they otherwise would.

The bad news is that Paley's company closed down in 1984,after only three years. Farmers resisted the new technology and long-terra backers were hard to find. But with the renewed concern about pesticides on produce, and refinements in infrared scanning, Paley hopes to get back into operation. Agriculture experts have no doubt the technology works. " This technique can be used on 75 percent of agricultural land in the United States," says George Oerther of Texas A & M. Ray Jackson, who recently retired from the Department of Agriculture, thinks remote infrared crop scanning could be adopted by the end of the decade. But only if Paley finds the financial backing which he failed to obtain 10 years ago.

【1】 Plants will emit an increased amount of heat when they are __________.

A. sprayed with pesticides

B. facing an infrared scanner

C. in poor physical condition

D. exposed to excessive sun rays

【2】 In order to apply pesticide spraying precisely, we can use infra-red scanning to __________.

A. estimate the damage to the crops

B. measure the size of the affected area

C. draw a color-coded map

D. locate the problem area

【3】 Farmers can save a considerable amount of pesticide by __________.

A. resorting to spot-spraying

B. consulting infrared scanning experts

C. transforming poisoned rain

D. detecting crop problems at an early stage

【4】 The application of infrared scanning technology to agriculture met with some difficulties. For example,__________.

A. the lack of official support

B. its high cost

C. the lack of financial support

D. its failure to help increase production

【5】 Infrared scanning technology may be brought back into operation because of __________.

A. the desire of farmers to improve the quality of their produce

B. growing concern about the excessive use of pesticides on crops

C. the forceful promotion by the Department of Agriculture

D. full support from agricultural experts

【题目】UCLA scientists report for the first time on the only known frog species that can communicate using purely ultrasonic(超声)calls, whose frequencies are too high to be heard by humans. Known as Huia cavitympanum, the frog lives only on the Southeast Asian island of Bomeo(婆罗洲).

Ultrasounds are high-pitched sounds more than 20 kilohertz(kHz) in frequency, which exceeds the upper limit of sounds detectable by humans and is far higher than the 5 to 8 kHz frequencies most amphibians (两栖动物),reptiles and birds are capable of hearing or producing. Key parts of the ear must be specially adapted to detect ultrasounds.

The frogs can hear sounds up to 38 kilohertz, the highest frequency that any amphibian species has been known to hear, the scientists report. Humans can hear up to about 20 kHz and typically talk at 2 or 3 kHz.

While most of the more than 5,000 frog species worldwide have eardrums that are flat on the side of the head, Huia cavitympanum has eardrums recessed in the side of the skull, similar to mammals.

Peter Narins, UCLA distinguished professor of physiological science and of ecology and evolutionary biology, and Victoria Arch, a UCLA graduate student in ecology and evolutionary biology, spent several nights in the remote area where the frogs live.

" We had very little information suggesting that they would be in this location," said Arch, lead author of the study. " We found them our first night out. "

The study was published on April 29 in the online journal PLOS ONE, a publication of the Public Library of Science, and is available at
http://dx. plos. org/10. 1371/journal, pone. 05413.

【1】 Huia cavitympanum mainly live __________.

A. in all over the world

B. in many parts of China

C. only on the Southeast Asian island of Borneo

D. only on the certain countries' marsh

【2】 This kind of new-found frog can hear each other with up to __________ kHz ultrasounds.

A. 2-3 B. 5 -8

C. more than 20 D. 38

【3】 If people can hear ultrasounds as frogs do, they should __________.

A. hear as frogs do carefully

B. have a pair of good enough ears like frogs

C. concentrate their energy on them

D. turn them into common sounds

【4】 According to the passage we can infer that __________.

A. the result of study is concluded not easily

B. some scientists have done a lot of work for the result

C. all the frogs have the ability with 38 kHz frequency

D. this kind of frogs is as important as animals

【5】 This passage probably appears __________.

A. on the newspaper B. on the textbook

C. on the website D. on the report

【题目】Like all animal species, plant species must spread their off-spring to suitable areas where they can grow and pass on their parents' genes. Young animals generally spread by walking or flying. Because plants don't have that ability, they must somehow hitchhike(搭顺风车). Some plant seeds scatter by blowing in the wind or floating on water. Many other plant species, though, trick an animal into carrying their seeds. How do they do this? They enclose the seeds within a tasty fruit and advertise the fruit's ripeness by its colour or smell. The hungry animal collects and swallows the fruit, walks or flies off, and later spits out the seeds somewhere far from its parent tree. Seeds can thereby be carried for thousands of miles. It may surprise you to learn that plant seeds can resist digestion. In fact, some seeds actually require passage through an animal's body before they can grow.

Wild strawberries offer a good example of hitchhiking tactics. When strawberry seeds are still young and not yet ready to be planted, the surrounding fruit is green, sour and hard. When the seeds finally mature, the berries turn red, sweet, and tender. The change in the berries'colour serves as a signal to birds which then eat the strawberries, fly off, and eventually spit out the seeds.

Naturally, strawberry plants didn't set out with a conscious intention of attracting birds only when their seeds were ready to be dispersed . Nor did birds set out with the intent of planting strawberries. Rather, strawberry plants evolved through natural selection. The sweeter and redder the final strawberry, the more birds spread its ripe seeds ; the greener and more sour the young strawberry, the fewer birds destroyed the seeds by eating berries before the seeds were ready.

【1】 What does the underlined word "dispersed" in the third para-graph mean?

A. Spread. B. Eaten. C. Born. D. Planted.

【2】 For plants, which of the following is NOT a way of spreading their offspring to suitable areas?

A. Hitchhiking.

B. Blowing in the wind.

C. Floating on water.

D. Tracking an animal.

【3】 Which strategy does the example of wild strawberries describe?

A. The conscious intent of attracting birds.

B. Spreading by walking.

C. Spreading by flying.

D. The strategy of taking a lift.

【4】 Why does the author describe how strawberry seeds are spread?

A. To show plants are good at adapting to the environment.

B. To show strawberry's special way.

C. To show the plant has different ways of spreading seeds.

D. To show the mystery of plant.

【5】 What's the passage mainly about?

A. How animals disperse offspring.

B. How plants disperse their offspring.

C. Plant evolution.

D. Plants'hitchhiking on animals.

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