This is adapted from an idea in NL Clay’s Exercises 12-13 (1933).
Attach appropriate negative prefixes to these words, e.g. grateful → ungrateful. There may be more than one answer for some words.
1 Adequate. Approve. Attentive. Balanced. Credible. Discreet. Dress. Fasten.
2 Formal. Inter. Involved. Man. Moderate. Obedient. Partial. Pious.
3 Please. Probable. Qualify. Respect. Satisfied. Secure. Suitable. Sure. Valid.
Disapprove. Disinter. Disobedient. Displease. Disqualify. Disrespect. Dissatisfied. Imbalanced. Immoderate. Impartial. Impious. Improbable. Inadequate. Inattentive. Incredible. Indiscreet. Informal. Invalid. Undress. Unfasten. Uninvolved. Unman. Unsuitable. Unsure.