Prefixes

1. Prefixes

He is sleeping in an uncomfortable position.

He is disobeying the rules.

2. Types of prefixes

There are different types of prefixes, but they can be grouped into two categories:

• Prefixes that allow us to form antonyms, that is, the opposite of a word. Although most of these prefixes can modify nouns, adverbs, and even verbs, we will focus on adjectives. Some of the most common ones are:
  

  Prefix	Root word	Opposite	Root word	Opposite
  IN-	Convenient	Inconvenient	Correct	Incorrect
  	Complete	Incomplete	Secure	Insecure
  IM-	Possible	Impossible	Polite	Impolite
  	Patient	Impatient	Mature	Immature
  UN-	Reliable	Unreliable	Fair	Unfair
  	Friendly	Unfriendly	Happy	Unhappy
  DIS-	Honest	Dishonet	Obedient	Disobedient
  	Satisfied	Dissatisfied	Organized	Disorganized
  IR-	Regular	Irregular	Responsible	Irresponsable
  	Relevant	Irrelevant	Resistible	Irresistible
  IL-	Legal	Illegal	Logical	Illogical
  	Legible	Illegible	Legitimate	Illegitimate

  There are no established rules for using these prefixes, so we will have to look in the dictionary to know which one we should use.
• Prefixes that have a meaning of their own. They can modify verbs, nouns and adjectives. Some of the most common ones are:
  

  Prefix	Root word	New word	Root word	New word
  ANTI-	Social	Antisocial	Virus	Antivirus
  EX-	Boyfriend	Ex-boyfriend	President	Ex-President
  MIS-	Spelt	Misspelt	Behave	Misbehave
  OVER-	Crowded	Overcrowded	Weight	Overweight
  RE-	Do	Redo	Paint	Repaint
  UNDER-	Cooked	Undercooked	Paid	Underpaid

Remember!