Using know

Know cannot be followed directly by an infinitive. Instead we use the structure know how to.

  • He knows how to operate a computer.
  • She knows how to make pizza.
  • He knows how to play the piano.
  • Do you know how to make Spanish omelettes?

Know is one of those verbs which cannot be usually used in continuous forms.

  • I know what you mean. (NOT I am knowing what you mean.)

Know can be used in the present perfect tense form.

  • I have known her for a long time.
  • We have known each other since our childhood.

Know can be followed by an object + infinitive in a very formal style.

  • I knew him to be a generous guy.

In a less formal and more natural style, we use a that-clause.

  • I knew that he was a generous guy.
  • I always knew that I couldn’t depend upon him.

Expressions with know

Know one’s own mind: be certain of one’s purpose, ideas etc.

Know what’s what: have common sense, good judgment, practical experience etc.

In the know: having information not shared by all

  • Those in the know don’t do things like that.

To the best of my knowledge: As far as I know

  • The information that I have given is true to the best of my knowledge.