Plausible
Implausible
Polite
Impolite
Scrupulous
Unscrupulous
Ripe
Unripe
Decisive
Indecisive
Accessible
Inaccessible
Normal
Abnormal
Orthodox
Unorthodox
Logical
Illogical
Replaceable
Irreplaceable
Practical
Impractical
Accurate
Inaccurate
Discreet
Indiscreet
Obedient
Disobedient
Loyal
Disloyal
Precise
Imprecise
Coherent
Incoherent
Legible
Illegible
Responsible
Irresponsible
Official
Unofficial
Emotional
Unemotional