Most birds find it safe to sleep in the trees, but _____ they have eggs or young chicks, they don’t use a nest.

 A. why   B. how   C.unless   D. where

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科目：高中英語 來源： 題型：

Most birds find it safe to sleep in the trees,but_______they have eggs or young chicks,they don’t use a nest.

A.why                                                             B.how

C.unless                                                          D.where

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科目：高中英語 來源： 題型：

.Most birds find it safe to sleep in the trees, but __________ they have eggs or young chicks, they don’t use a nest.

A. why    B. how

C. unless D. where

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科目：高中英語 來源：2012-2013學(xué)年江蘇省沭陽縣高二下學(xué)期期中調(diào)研測(cè)試英語試卷（帶解析） 題型：完型填空

完形填空（共20小題；每小題1分，滿分20分）
請(qǐng)認(rèn)真閱讀下面短文，從短文后各題所給的A、B、C、D四個(gè)選項(xiàng)中，選出最佳選項(xiàng)，并在答題卡上將該項(xiàng)涂黑。
Most people think of birds as feathered animals that fly. Scientists,   36 , do not define (給…下定義) birds as animals that fly, because some birds do not. Of the 10,000 or so species of birds, 46 cannot   37 . Flight plays a key role in   38  for most birds. It allows them to find food over a   39  area and to get away from enemies. Ancestors of flightless birds may have   40   their ability to fly because they had no regular predators (捕食者) or did not need to fly to find food. Rather than fly, some of these birds developed other   41  to catch food and avoid enemies. Two examples of   42  birds are penguins and ostriches.
  43  birds that fly, penguins do not have wide wings or large feathers. In order to catch the fish they feed on, penguins use their powerful wings to swim   44 . And when they swim,  they look as if they are flying through the water. The   45  of penguins’ bodies makes it possible for them to dive deep underwater,  46  their thick feathers protect them from the cold.
Ostriches are known for their long legs, long necks, and large size. To   47  themselves, they stay in groups and use their excellent sight and hearing to   48  enemies. As soon as    49  approaches, they can run at a speed of more than 65 kilometers per hour to   50  . In addition to using their strong legs to run, they can kick powerfully. 
Not all flightless birds have been   51  in protecting themselves. Flightless birds on some islands had no enemies until people   52 . These birds were hunted and easily caught by people and the animals   53  by people. Human land development has   54  the habitats of some birds. A number of flightless birds   55  because they were unable to adapt to new conditions and new enemies.

【小題1】
A．thusB．howeverC．thereforeD．otherwise
【小題2】
A．standB．flyC．hearD．sing
【小題3】
A．growthB．communicationC．healthD．survival
【小題4】
A．wideB．familiarC．crowdedD．special
【小題5】
A．developedB．improvedC．lostD．proved
【小題6】
A．partsB．habitsC．waysD．tools
【小題7】
A．wildB．interestingC．rareD．flightless
【小題8】
A．Instead ofB．Because ofC．BesidesD．Unlike
【小題9】
A．quicklyB．carefullyC．differentlyD．gradually
【小題10】
A．shapeB．color C．bone D．skin
【小題11】
A．ifB．a(chǎn)ndC．butD．so
【小題12】
A．helpB．feedC．protectD．hide
【小題13】
A．killB．noticeC．confuseD．frighten
【小題14】
A．dawnB．darknessC．dangerD．food
【小題15】
A．lookB．escapeC．moveD．fight
【小題16】
A．successfulB．naturalC．unusualD．positive
【小題17】
A．realizedB．a(chǎn)ctedC．stoppedD．a(chǎn)rrived
【小題18】
A．broughtB．foundC．boughtD．hunted
【小題19】
A．providedB．formedC．destroyedD．controlled
【小題20】
A．flew awayB．watched outC．gave awayD．died out

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科目：高中英語 來源：2013屆吉林省長春市十一中高三上學(xué)期期初考試英語試卷（帶解析） 題型：閱讀理解

When many people see birds cleaning their feathers, they attribute it to vanity on the part of the bird. But, in reality, what they are doing is maintaining their wings, the instruments that they depend on for safe flight. If a bird’s wings are not in perfect condition, the bird either won’t be able to fly or won’t be able to control its flight. That is why after a long flight and even throughout the day, you will see them cleaning their feathers.
Most birds, if they get a chance, will take a bath at least once a day. They do this to get rid of the dust that has accumulated in their feathers throughout their flight s during the day. In dry or desert areas, birds will not always be able to find water in which to bath, but they still need to clean their feathers. What many birds will do is to take dust baths. They will roll around in dust until it covers their feathers. They will stand up, shaking the dust out, and then clean their feathers with their beaks (鳥嘴) as usual.
Baths are important for another reason. During the course of the day and night, many parasites (寄生蟲) are attracted to birds. Bugs, mites, fleas and so on will try to reach birds and suck from their blood. Daily baths help to keep the parasites to a minimum.
Some birds, especially those that spend a lot of time in or around water, have skin glands (皮膚腺) that produce oil. After bathing, these birds will squeeze the glands to spread the oil over their wings to keep them free of water.
If you are a bird lover and have bird houses in your yard, it can be good to go to the extra step, providing a bird bath. Once the birds in your neighborhood discover it, you will be surprised at how popular it becomes as they periodically stop by to take their daily bath.
【小題1】What’s the passage mainly about?

A．How birds clean themselves.B．What birds enjoy doing.
C．Why baths matter so much to birds.D．What bird lovers should do.
【小題2】What does the underlined part in Para 1 probably mean?
A．Most people think it good for birds to clean their feathers.
B．Most people show much interest in how birds clean themselves.
C．Most people believe that birds’ keeping themselves clean is necessary.
D．Most people think birds’ cleaning their feathers of no practical significance.
【小題3】According to Para 3, birds’ feather cleaning _____.
A．helps keep them healthyB．keeps them free of any parasite
C．makes them more attractiveD．helps them relax enough
【小題4】In the last paragraph, the author further reminds us that _____ .
A．we should love birds as much as possible
B．birds enjoy cleaning themselves by bathing
C．we can be good bird lovers by bathing birds
D．birds like to come close to the people in a yard

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科目：高中英語 來源：2007年高考試題（湖南卷）解析版 題型：單項(xiàng)填空

 Most birds find it safe to sleep in the trees,but_______they have eggs or young chicks,they don’t use a nest.

A.why                                   B.how

C.unless                                    D.where

 

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