Negative Prefixes

We use the negative prefixes un- / in- /im- /il- /ir-

For example:

John and James are brothers. John is reliable, you can trust him to do anything you ask. James, on the other hand, is unreliable, you cannot rely on him.

By adding un to reliable we change the meaning of the word to not reliable.

Dis gives the adjective the opposite meaning: "I know you all agree with the plan, but I still disagree."

Use un- prefix before words that start with a vowel or consonant.
Use il- prefix before words that start i: illegal.
Use im- prefix before words that start with m or p: impossible.
Use ir- prefix before words that start with r: irregular.
Use in- prefix with words that start with consonants and vowels, but not i or u.

Now choose the correct word to complete each sentence:

• 1) They say he has a ___ face.
  
  dishonest
  inhonest
  ilhonest
  
  
• 2) I have an ___ fear of mice.
  
  inrational
  irrational
  disrational
  
  
• 3) The Joker character in Batman is ___.
  
  ilsane
  irsane
  insane
  
  
• 4) In the UK it's ___ to smoke in bars and restaurants.
  
  inlegal
  imlegal
  illegal
  
  
• 5) It's ___ that we have to work while they are on holiday.
  
  unfair
  disfair
  infair
  
  
• 6) I am too ___ to go fishing.
  
  inpatient
  impatient
  unpatient
  
  
• 7) He's so ___ even after all the help we gave him.
  
  ungrateful
  ingrateful
  imgrateful
  
  
• 8) He still acts like a child, he's so ___.
  
  irmature
  immature
  inmature
  
  
• 9) I think the information in this report is ___. It doesn't look right.
  
  inaccurate
  iraccurate
  unaccurate
  
  
• 10) His attempt to break the world record was ___.
  
  insuccessful
  unsuccessful
  dissuccessful