【单选题】(2013·北京,26)I have an appointment ________ Dr.Smith, but I need to change it.
【单选题】Shall we all drive to the party________ so we don’t get lost?
【单选题】I have an appointment ________ Dr.Smith,but I need to change it. (2013·北京,26)
【简答题】现代通信主要由卫星通信和________ 通信两种方式组成;通信卫星转发信号是通过 ________ 来实现的;图是通信卫星在赤道上空高的运行轨道上的图片,它与地球同步转动,则卫星相对地面是________________。
【单选题】I have an appointment( )Dr. Smith, but I need to change it.
【单选题】Shall we all drive to the party________ so we don’t get lost?