to not know; to be unaware of or have no idea about

(bound form) used after a verb, adjective, or noun to represent the person or thing performing an action or possessing a quality; translates as "-er", "-ist", or "one who"

Negative adverb used before verbs, adjectives, and other adverbs to indicate negation; also used as a bound-form prefix to form terms with opposite meanings

to put the blame on someone; to condemn or reproach