• 2022-05-30
    According to the passage, the invention of the visible - light microscope allowed scientists to ______.
    A: see viruses directly
    B: develop the electron microscope later on
    C: understand more about the distribution of the chemical elements
    D: discover single-celled plants anal animals they had never seen before
  • D

    内容

    • 0

      According to the passage, scientists have discovered that influenza viruses ______ . A: cause ill health in wild birds B: do not always cause symptoms in birds C: are rarely present in wild birds D: change when transferred from animals to man

    • 1

      ——Do you like the movie Harry Potter?<br/>——Sorry. I ____ that movie. A: never saw B: never see C: had never seen D: have never seen

    • 2

      The resolution of a light microscope is() A: 2.0nm B: 0.2nm C: 0.2μm D: 2.0μm E: 5.0 nm

    • 3

      The witness told the court that he _____ the accused before. A: had never seen B: had ever seen C: hasn't seen D: didn't see

    • 4

      Nowhere else in the world ______ more beautiful scenery than in Switzerland. A: you can see B: you had seen C: can you see D: had you seen