Grammar Collection: DISILIMINIRUN Adjectives and Prefixes
Most adjectives can be made negative with the use of a short prefix, dis-, il-, im-, in-, ir- and un-. For example, satisfied becomes dissatisfied, legal becomes illegal and practical becomes impractical.
You can teach your class the prefixes, and what adjectives to use them with, but (as usual) practicing them can be the hardest part.
DISILIMINIRUN is a board game with the adjectives, all your students need to do is decide which prefix to use and then use the negative form of the word in a sentence, simple.