若二次根式$\sqrt{2x-1}$有意义，则x的取值范围是（　　）

A. How about Sunday afternoon?    B. I'd love to.

C. This is Allen speaking!   D. Can you give me a hand?

E. That is Allen.     F. This is Mike.     G. Thank you.

Allen: Hello!

Mike: Hello ! ____. May I speak to Allen, please?

Allen:____.

Mike: Hi, Allen. How are you?

Allen: Fine, thanks. And you?

Mike: I'm fine. ____. Allen, I need some help.

Allen: Sure. ____

Mike: There is something wrong with my computer. Can you mend(修理) it?

Allen: Certainly, but not today. ____

Mike: OK. Thanks a lot. See you then.

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                                                                                           张元饲弃狗
      有犬为人所弃，惶惶于阡陌间。张元见之，即收而养之。其叔父怒曰：“何用此为？”将欲逐之。元乞求毋弃，曰：“有生之物，莫不重其性命。若天生天杀，乃自然之理。今犬为人所弃而死，非道也。若见而不收养，无仁心也。”叔父感其言，遂许焉。
      明年，犬随叔父夜行。叔父为蛇所啮，仆地不得行。犬亟奔至家，汪汪之声不停。张元怪之，随犬出门，见叔父已不省人事。速延医治之，不日而愈。自此，叔父视犬如亲。