• ascertain

    When you ascertain the truth of something, you determine or find it out for sure.

  • certain

    If you are certain about something, you are sure or have no doubt about it.

  • certainty

    the state of being certain

  • certifiable

    fit to be certified as insane (and treated accordingly)

  • certificate

    present someone with a certificate

  • certification

    the act of certifying or bestowing a franchise on

  • certify

    provide evidence for

  • uncertain

    lacking or indicating lack of confidence or assurance

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