1. necessary unnecessary Answer: unnecessary
    legal illegal Answer: illegal
    organized disorganized Answer: disorganized
    impressed unimpressed Answer: unimpressed
    logical illogical Answer: illogical
    regular irregular Answer: irregular
    enthusiastic unenthusiastic Answer: unenthusiastic
    honest dishonest Answer: dishonest
    mature immature Answer: immature
    patient impatient Answer: impatient
    just unjust Answer: unjust
    grateful ungrateful Answer: ungrateful
    loyal disloyal Answer: disloyal
    legible illegible Answer: illegible
    edible inedible Answer: inedible
    literate illiterate Answer: illiterate
    replaceable irreplaceable Answer: irreplaceable
    reversible irreversible Answer: irreversible
    sincere insincere Answer: insincere
    agreeable disagreeable Answer: disagreeable