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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.


  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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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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【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
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A.dawnB.darknessC.dangerD.food
【小題15】
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A.realizedB.a(chǎn)ctedC.stoppedD.a(chǎn)rrived
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A.broughtB.foundC.boughtD.hunted
【小題19】
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