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verb [never progressive] know pronunciation in British English /nəʊ/
Word Forms
present tense
present participleknowing
past tenseknew
past participleknown
  1. 1
    [intransitive/transitive] to have learned or found out about something

    ‘Have they arrived yet?’ ‘I don’t know.’

    If you don’t know the answer, just guess.

    How do you know my name?

    know (that):

    I knew she wasn’t really happy.

    know what/where/how etc:

    I don’t know where the money’s coming from.

    know if:

    I need to know if she’s made a decision yet.

    know something about someone/something:

    I don’t know anything about it.

    know something for sure/for certain/for a fact:

    We know for a fact that the fire was started deliberately.

    know something from experience:

    We know from experience that unemployment makes the problem worse.

    1. b.
      [transitive] [often passive] used about things that most people think or believe are true

      The ancient city is known to have existed in the region.

      know someone/something to be something:

      The pilots were experienced and known to be very competent.

      know someone/something to do something:

      Some drugs are known to cause damage to unborn children.

  2. 3
    [transitive] to use a particular name for someone or something
    know someone/something as something:

    The village was known as Garden Mill.

    know someone/something by something:

    They know all their tutors by their first names.

  3. 4
    [transitive] to remember or recognize someone because of a particular skill or quality that they have
    know someone as/for something:

    He was best known as a painter.

    We know her mostly for her love poetry.

  4. 5
    [transitive] to experience something

    It was the only comfort and warmth she had ever known.

    have never known someone (to) do something:

    I’ve never known her to make a joke.

  5. 7
    [intransitive/transitive] to feel certain about something
    know (that):

    She knew it was Steven before she’d picked up the phone.

  6. 8
    [transitive] to recognize someone or something

    It was Henry: I would have known him anywhere.


phrasal verbs



… a teaching method in which groups of children learn independently using a computer linked to the internet

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a derogatory word used for referring to people in the banking and investment industry who are thought of as taking serious risks in order to increase their own earnings …

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