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


  1. A.
    why
  2. B.
    how
  3. C.
    unless
  4. D.
    where
C
本題考查連詞的用法。unless表“除非”，除非它們下蛋或撫育雛鳥，它們不去使用巢穴。
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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.

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完形填空（共20小題；每小題1分，滿分20分）
請認(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. 
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【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】
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【小題1】What’s the passage mainly about?

A．How birds clean themselves.B．What birds enjoy doing.
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【小題2】What does the underlined part in Para 1 probably mean?
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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
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 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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