To affirm to be correct, true, or genuine.
To certify in an official capacity.
To put under oath.
To supply or be evidence of.
To certify by signature or oath.
To perceive the truth or factuality of; to be certain of or that.
To experience.
To understand or have a grasp of through experience or study.
To be or become aware or cognizant.
To be able to play or perform (a song or other piece of music).
To be acquainted or familiar with; to have encountered.
To be aware of; to be cognizant of.
To recognize as the same (as someone or something previously encountered) after an absence or change.
To have knowledge; to have information, be informed.
Knowledge; the state of knowing.
Knowledge; the state of knowing; now confined to the fixed phrase ‘in the know’