In this lesson students practice using negative prefixes. Go over the chart with your students and have them complete the practice exercises.
| Prefix | Meaning | Examples and Notes |
| un | not; the opposite of | unusual, unfriendly, unimportant “un” is the most common negative prefix. |
| in | not; the opposite of | inefficient, inappropriate, ineffective “in” is the second most common negative prefix. Many words that begin with “in” do not contain prefixes (insist, initially, insult, for example). Also, the prefix “in” has two meanings. It can be used to mean “not; the opposite of” or “within” (inside, in-house, etc.). |
| im | not; the opposite of | impossible, imperfect, immeasurable, impartial Words that take “im” as a negative prefix always begin with an “m” or a “p” (imbalance is the one exception). However, not all adjectives that start with an “m” or “p” take “im” as a negative prefix (unmistakable, unpopular, unimportant, for example). |
| il | not; the opposite of | illegal, illegitimate, illegible, illiterate, illogical Words that take “il” as the negative prefix always begin with the letter “i”. However, not all words that begin with “i” take “il” as a negative prefix (unlicensed, for example). |
| ir | not; the opposite of | irregular, irrational, irresponsible Words that take “ir” as a negative prefix always begin with the letter “r”. |
| non | not | nonsense, nondairy, nonfiction, nonprofit, nontoxic |
| a | not | atypical, apolitical, asymmetrical |
| de | used to communicate the reversal of an action. | deactivate, deconstruct, declassify, decompose, deform |
| dis | 1. used to communicate the reversal of an action. 2. not; the opposite of |
1. disconnect, disable 2. disagree, disapprove, dishonest |
| mis | wrongly | misfire, misguide, mislead, misinform |
| anti | against | antisocial, anti-inflammatory |
| dys | bad or difficult | dysfunctional, dyslexic |
Negative Prefix Practice 1: un, in, im, il, and ir
Cut out the words. Have students separate the words into the following categories:
1. words that take “un” as a negative prefix
2. words that take “in” as a negative prefix
3. words that take “im” as a negative prefix
4. words that take “il” as a negative prefix
5. words that take “ir” as a negative prefix
| able | equal | secure | professional | rational | perfect | believable |
| responsible | literate | accurate | accessible | sufficient | regular | clear |
| do | complete | fair | common | precise | fortunate | important |
| relevant | polite | aware | pure | efficient | grateful | justifiable |
| direct | active | valid | veil | mature | consistent | reversible |
| comfortable | identified | effective | friendly | capable | known | achievable |
| legal | reliable | logical | conspicuous | appropriate | employed | usual |
| expected | reasonable | flexible | willing | legitimate | adequate | certain |
| patient | stable | cover | replaceable | significant | possible | cooperative |
Negative Prefix Practice 2: non, a, de, dis, mis, anti, and dys
Have students fill in the blanks with a word containing a negative prefix.
non
We flew from Tokyo to London without stopping in any other cities. Our flight was _________.
I’m sorry, you can’t smoke here. This is a _________ area.
a
Is this uncommon? Yes, it’s extremely _________.
I don’t understand why the Republicans and Democrats are blaming each other for this. To me, it’s definitely an _________ issue.
de
Is there any way to _________ the alarm on my car? It keeps going off in the middle of the night.
I’m drinking a lot of water because I don’t want to get __________.
Yelling at your employees is a good way to _________them.
dis
One of the _________ of operating in the U.S. is the high labor costs.
Some of the runners were _________ for using performance-enhancing drugs.
mis
It might not have been an outright lie, but what he said was definitely _________.
You should always use spell checker to make sure you haven’t _________ anything.
When speaking English to non-native speakers, you should avoid using obscure idioms to make sure they don’t _________ you.
anti
The doctor prescribed me some _________ to get rid of the infection.
My roommate has been very _________ lately. He spends all his time in his room playing video games and never comes out to talk.
dys
He comes from a _________ family, but he became successful anyway.
Are you optimistic about the future? Do you think it will be a utopia or a _________ ?
Answers:
non-stop, non-smoking, atypical, apolitical, deactivate, dehydrated, demotivate, disadvantages, disqualified, misleading, misspelled, misunderstand, antibiotics, antisocial, dysfunctional, dystopia