Have you ever wondered whether you should say impolite or unpolite, illegal or unlegal, incorrect or uncorrect? English uses several negative prefixes and suffixes to create words with an opposite or negative meaning. Unfortunately, there is no single prefix that works with every word, so it is important to learn the combinations that are normally used.

Compare:

Understanding negative prefixes and suffixes in English is particularly useful for learners preparing for B2 First and C1 Advanced, where word formation is frequently tested in Reading and Use of English.

In this lesson, we will look at the most useful negative prefixes and suffixes, their meanings and common examples.

Prefix UN-

Un- is one of the most common negative prefixes in English. It usually means not or the opposite of.

It is particularly common with adjectives.

It can also be used with some verbs to show that an action is reversed.

Prefix IN-

The prefix in- often means not.

It occurs mainly with adjectives, particularly words of Latin origin.

The form of in- sometimes changes depending on the first letter of the word that follows it. This gives us im-, il- and ir-.

Prefix IM-

Before words beginning with m or p, in- often changes to im-.

Examples:

It would be impossible to finish all the work today.

It was impolite of him to interrupt.

Prefix IL-

Before words beginning with l, in- often becomes il-.

Prefix IR-

Before words beginning with r, in- often becomes ir-.

Prefix DIS-

The prefix dis- can mean not, the opposite of or the reverse of an action.

It is used with adjectives, nouns and verbs.

DIS- with adjectives

DIS- with verbs

DIS- with nouns

Prefix NON-

The prefix non- means not or without. It is often more neutral than prefixes such as un- or dis-.

It is commonly used with nouns and adjectives.

Prefix MIS-

Mis- is slightly different from prefixes such as un- and in-.

It usually means wrongly, badly or incorrectly rather than simply not.

Prefix ANTI-

The prefix anti- usually means against, opposed to or intended to prevent something.

It is therefore not a negative prefix in exactly the same way as un- or in-, but it often expresses opposition.

Prefix A-

The prefix a- can sometimes express the meaning not, without or lacking.

It occurs in a relatively small number of words, so it is better to learn these words individually.

What About AB-, AN- and IG-?

You may sometimes see ab-, an- and ig- included in lists of negative prefixes.

However, for learners of modern English, it is more useful to treat words such as these as individual vocabulary items.

These prefixes are not productive in modern everyday English, so learners should not try to create new words with them.

For practical B2–C1 English, it is much more useful to concentrate on:

un-, in-, im-, il-, ir-, dis-, non- and mis-

Negative Suffixes in English

English has fewer suffixes that express a negative idea, but one is especially important: -less.

Suffix -LESS

The suffix -less means without or lacking something.

It is usually added to nouns to form adjectives.

Notice that -less does not always create the exact opposite of a word. It generally means without the thing expressed by the noun.

-FUL and -LESS

Some nouns can take both -ful and -less, producing contrasting adjectives.

However, this pattern does not work with every word.

For example:

beautiful ✓

beautiless ✗

Again, it is safer to learn complete word families rather than inventing forms.

Common Mistakes with Negative Prefixes

Negative prefixes are a common source of mistakes because learners sometimes translate directly from their own language or choose a prefix because it seems logical.

These examples show why it is useful to learn words in families.

For example:

responsible → irresponsible → responsibility → irresponsibility

rather than learning responsible on its own.

Negative Prefixes and Cambridge Exams

Negative prefixes are particularly important in the Word Formation section of Cambridge B2 First and C1 Advanced Reading and Use of English.

You may be given a base word such as:

POSSIBLE

and need to complete a sentence:

It would be __________ to complete the project in one afternoon.

The answer is:

impossible

You may also need to make more than one change.

This is why learning word families is so useful.

When you learn a new adjective, try to record its negative form as well.

Preparing for C1 Advanced?

If you are preparing for C1 Advanced Reading and Use of English, you need much more than individual vocabulary items. You need to recognise word families, collocations, fixed expressions and grammatical patterns quickly and accurately.

The C1 Advanced Use of English Complete Collection gives you focused practice with the key task types you will meet in the exam, including Multiple-Choice Cloze, Open Cloze and Key Word Transformations.

Negative Prefixes and Suffixes in English Practice Worksheet

Quiz

Quick Reference Table

Here is a useful summary of the most common negative prefixes and suffixes in English.

Final Tip

Negative prefixes and suffixes in English may seem like a small area of vocabulary, but they can help you build and recognise hundreds of English words.

The important thing is not to memorise a list of prefixes and attach them randomly to words. Instead, learn common word families and combinations.

Once these combinations become familiar, choosing the correct form will become much more natural in conversation, writing and Cambridge exams.