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9. It is reported that New Culture Square ________ in our city next year.

  A. will be built   B. were built    C. have built     D. will build

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8. Each time tourists travel to Beijing, they _________ the Forbidden City.

  A. will be shown up   B. will be shown around   C. will show around  D. will show to

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7. Not only Jim but also his parents _________ a few interesting places since they came to China.

  A. will visit    B. has visited     C. have visited    D. visited

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6. Please __________ the water when you brush your teeth.

  A. take down    B. turn up      C. take away     D. turn off

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5. Some people waste too much water. They don’t believe that it can _________ some day.

  A. keep out    B. run out      C. be run out     D. run out of

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4. I think we must give up using plastic bags to ___________ our earth.

  A. produce    B. protect       C. provide     D. pollute

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3. Driving after drinking wine ________ in China.

  A. allows     B. doesn’t allow    C. is allowed    D. isn’t allowed

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2. The government should stop them from _______ trees in the forest.

  A. cutting down     B. putting down     C. taking down    D. letting down

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一、单项选择

1. —What should I do to live _____ green life?—I think you go by _____ bike instead of driving your car.

  A. a; a     B. the; /      C. a; /     D. /; /

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24.(本小题14分)

解:(1)将x=0代入y=(x-2)2+1,得y=5.

则抛物线y=(x-2)2+1与y轴的交点A的坐标为(0,5).  ………………1分

抛物线y=(x-2)2+1的顶点B的坐标为(2,1).     ………………2分

设抛物线y=(x-2)2+1的友好直线AB的表达式为y=kx+b,

解,得          …………………………4分

∴抛物线y=(x-2)2+1的友好直线AB的表达式为y=-2x+5.  ………5分

抛物线y=(x-2)2+1的友好四边形的面积为20.    ……………………6分

(2)如图,抛物线的顶点为B(h,k),

作BE⊥AC于点E,

由题意得四边形ABCD是平行四边形,

直线y=x-3与y轴的交点A的坐标为(0,-3),

所以,点C的坐标为(0,3),可得:AC=6.  …………8分

∵平行四边形ABCD的面积为12,

∴SABC=6即SABC=AC•BE=6,

∴BE=2,            …………………………9分

∵h>0,即顶点B在y轴的右侧,∴h=2.

∵点b在直线y=x-3上,

∴顶点B的坐标为(2,-1),        ………………………………10分

又抛物线经过点A(0,-3),

a=-,∴抛物线表达式为y=.   …………………………11分

(3)①当抛物线的友好四边形ABCD是菱形时,如图.

AC⊥BD,OA=OC,OB=OD,

∵AC在y轴上,AC⊥BD,

∴此时BD在x轴上,∴点B的坐标为(h,0).  …………12分

∵点B在直线y=-2x+m上,

∴把y=0代入y=-2x+m,得x=.

∴抛物线顶点B的坐标为(,0). ………………………13分

②当抛物线的友好四边形ABCD是矩形时,

∴抛物线顶点B的坐标为B().……………14分

 

说明:以上各题的其他解法请参照此标准评分.

 

 

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