1. Negation:
* un-, in-, im-, ir-, non-, dis-
* unhappy: not happy
* inactive: not active
* impossible: not possible
* irregular: not regular
* nonexistent: not existing
* disagree: not agree
2. Reversal or Opposition:
* de-, anti-, counter-
* deactivate: reverse the action of activate
* antibacterial: against bacteria
* counterclockwise: in the opposite direction of clockwise
3. Location or Position:
* pre-, post-, inter-, intra-, sub-, super-, trans-
* pregame: before the game
* post-mortem: after death
* interstate: between states
* intracellular: within a cell
* submarine: below the surface of the water
* superhuman: above human abilities
* transatlantic: across the Atlantic Ocean
4. Quantity or Degree:
* over-, under-, semi-, hyper-, sub-, multi-
* overwhelmed: excessively burdened
* underestimate: to estimate something as being less than it is
* semiannual: occurring twice a year
* hyperactive: excessively active
* substandard: below the usual standard
* multifaceted: having many aspects
5. Time or Repetition:
* re-, fore-, bi-, tri-, mono-
* redo: do again
* forewarn: warn in advance
* bilingual: able to speak two languages
* tricycle: a vehicle with three wheels
* monologue: a speech by one person
6. Other Meanings:
* auto-: self
* co-: with, together
* pro-: in favor of
* micro-: very small
* macro-: large
Example:
* The word "happy" is positive. Adding the prefix "un-" makes it negative: "unhappy".
Remember: The meaning of the prefix can vary slightly depending on the context and the base word it's attached to.