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26. - Ring me at six tomorrow morning, will you?

  - Why that early? I _____.

  A. will be sleeping       B. have slept         C. have been sleeping   D. will sleep

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25. Mike _______ have known the solutions to this problem, or he would have told us.

  A. mustn’t            B. shouldn’t         C. can’t            D. needn’t

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24. He apologized for his mistake, saying that he ___________no offence.

  A. intended            B. supposed         C. considered         D. pretended

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23. He was rejected for the job vacancy because he couldn’t be ______even for the

  interview. 

  A. responsible        B. beneficial       C. punctual         D. regular

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22. -I think we have to solve _____ problem of air quality for the Great International Art Festival held in our city next year.

  - Yes, and the government is trying to think of _____ way out and there is more than one 

  solution.

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

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第一节 单项填空(共15小题;每小题1分,满分15分)

从A, B,C,D四个选项中,选出可以填入空白处的最佳选项,并在答题卡上将该项涂黑。

21. -Excuse me, can you spare me a few minutes?

  -_________?

  A. What’s on          B. What’s up         C. What is it     D. What’s more

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34.(11分) 白花三叶草有叶片内含氰(有剧毒)和不含氰的两个稳定遗传的品种,已知白花三叶草叶片内氰化物是经下列途径产生的(如下图)。

(1)若某一品系基因突变后,叶片内不含氰,但含氰糖苷较多,发生突变的基因是__________

(2)若两个不含氰的品种杂交,F1全部含氰,F1自交得到F2。写出亲代的基因型_________     ; F2个体的表现型及其比例是______    ____;F2含氰个体中能稳定遗传的个体所占的比例是______    ____。

(3)现有HhDd个体,怎样快速培育出含氰且能稳定遗传的个体?简要写出培育过程

①______                           _  ___;

②______                             ___;

③_______                             

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33.(11分)玉米种子在黑暗中萌发,测定胚芽鞘与幼根中各部分生长素含量,结果如图A所示。请据图分析回答:

(1)从图中观察玉米种子萌发过程中,合成生长素旺盛的部位是_______和_______。

(2)调节根尖伸长区细胞伸长的生长素来源于根尖的_____     __。

(3)切除玉米胚芽鞘的顶端,然后在其左侧放置含有不同浓度生长素的琼脂块,保持在黑暗中12h。胚芽鞘可能向右弯曲,弯曲角度如图B所示。生长素浓度与弯曲角度关系如图C 所示。实验要在黑暗中进行的原因是_________________。

(4)请分析说明实验结果:_______________               __。

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