Prefixes Worksheet for practicing word formation by adding prefixes to base words.

- clockwise → unclockwise
- possible → impossible
- happy → unhappy
- code → decode
- fiction → nonfiction
- view → preview
- play → replay
- obey → disobey
- healthy → unhealthy
- serve → preserve
- behave → misbehave
- place → replace
- lucky → unlucky
- visible → invisible
- mind → remind
- prove → disprove
- frost → defrost
- cover → uncover
- sent → resent
- historic → prehistoric
- sense → nonsense
- fix → unfixed (or re-fix, depending on context — “unfix” is less common; “refix” may be intended)
- legal → illegal
- connect → disconnect
- appear → reappear
- able → unable
- wind → rewind
- honest → dishonest
- chief → archchief (or unchief — “archchief” is more common for elevated status; “unchief” not standard — perhaps “dechief” or “anti-chief” if forced, but this is a weak fit)
- fair → unfair

Note: Some words like “unfixed,” “unchief,” or “refix” are not standard English. For “fix,” “unfix” means to undo a fix, which is valid. For “chief,” “archchief” is acceptable in some contexts, but “unchief” is not standard — the worksheet may expect “anti-chief” or simply leave it blank. The most natural and common prefixes are used where possible.