Negative prefixes

In English, one way to make negative statements is by adding negative prefixes to nouns, adjectives, and verbs. Here are some English negative prefixes: a–, dis–, il–, im–, in-, ir–, non–, un–.

For example, the prefix un- can be attached to the adjective happy to create the negative adjective unhappy. Or you can use the negative adverb not. Note that there is no difference in meaning between these two forms.

Tom is happy.		Tom is unhappy.		Tom is not happy.

Words that take a– as a negative prefix always begin with a consonant.

affirmative		negative
political		apolitical
sexual		asexual
theist		atheist

Words that take dis– as a negative prefix may begin with a vowel or a consonant.

affirmative		negative
agree		disagree
comfort		discomfort
mount		dismount
orient		disorient

Words that take il– as a negative prefix always begin with the letter l.

affirmative		negative
legal		illegal
legible		illegible
literate		illiterate
logical		illogical

Words that take im– as a negative prefix always begin with the letter m or p.

affirmative		negative
mobile		immobile
moral		immoral
perfect		imperfect
possible		impossible

Words that take in– as a negative prefix can begin with a vowel (except i or u) or a consonant.

affirmative		negative
accurate		inaccurate
eligible		ineligible
organic		inorganic
decent		indecent
sane		insane

Note: There are many words that begin with in– that are not words with a negative prefix. For example:

word		does not mean
incline		not cline
indulge		not dulge
insist		not sist
invoke		not voke

Words that take ir– as a negative prefix always begin with the letter r.

affirmative		negative
rational		irrational
reconcilable		irreconcilable
regular		irregular
resistible		irresistible

Words that take non– as a negative prefix may begin with a vowel or a consonant.

affirmative		negative
conformist		nonconformist
essential		nonessential
fiction		nonfiction
sense		nonsense

Words that take un– as a negative prefix may begin with a vowel or consonant.

affirmative		negative
able		unable
interesting		uninteresting
usual		unusual
comfortable		uncomfortable
helpful		unhelpful
prepared		unprepared

Remember, not all words that appear to have a negative prefix are negative.

word		does not mean
alike		not like
discuss		not cuss
universe		not iverse
illuminate		not luminate
important		not portant
involve		not volve
irrigate		not rigate

1. legal: There is no doubt that cannabis will remain an ______________ drug for the foreseeable future.
2. possible: It was quite _________________ for us to drive all the way from Paris to Madrid in one day.
3. successful: He made an ________________ attempt to climb the highest mountain in the range.
4. responsible: To take the boat out with four children under the age of ten and with no life jackets on board was quite ________________ of him.
5. appropriate: The dress she was wearing was quite _________________ for the occasion.
6. polite: It was very ________________ of him to insult his mother in front of his aunt.
7. religious: They were a completely _________________ family and I never thought that one day I would marry one of the daughters.
8. honest: As a politician he was __________________ and it was not long before nobody trusted him.
9. perfect: The goods were ________________ and had to be returned to the store we bought them from.
10. contented: She was __________________ with her life and decided that things had to change.

Go to answers

Exercise 1
Exercise 2
Exercise 3
Exercise 4