Secure
Insecure
Compatible
Incompatible
Capable
Incapable
Competent
Incompetent
Correct
Incorrect
Considerate
Inconsiderate
Available
Unavailable
Desirable
Undesirable
Known
Unknown
Friendly
Unfriendly
Discovered
Undiscovered
Likely
Unlikely
Likeable
Unlikeable
Practical
Unpractical
Easy
Uneasy
Political
Unpolitical