【单选题】【消耗次数:1】
The president has an ____________ secretary.
extensive
efficient
effective
expensive
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相关题目
【单选题】 I asked the secretary if there were ______ tickets but she had only the expensive ______.
①  one, ones
②  any, one
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④  any, ones
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②  much
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①  healthy
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①  motion
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①  are speaking
②  is speaking
③  were making a speech
④  have a speech
【判断题】 The secretary and the manager was present at the meeting yesterday.
①  正确
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【单选题】 Thirty dollars ___ too expensive.
①  are
②  is
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①  proved
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【单选题】 已知X与Y相互独立,且D(X)=3,D(Y)=4,则D(2X-3Y)= ( )
①  -24
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【单选题】 已知X与Y相互独立,且D(X)=3,D(Y)=4,则D(2X-3Y)= ( )
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