Suffix and Prefix — Rules, List & Exercise

A prefix is added before a root word and usually changes its meaning (happy → unhappy); a suffix is added after it and usually changes its part of speech (happy → happiness). In the exam you are given a root word and a blank, and the sentence tells you which part of speech is needed — so identify the word class the blank requires first, then choose the affix that produces it.

Where it is set: SSC & HSC English 2nd Paper — Grammar

What each one does

A prefix goes before the root word and a suffix goes after it, but the difference matters more than position. A prefix normally changes the meaning of a word while leaving its part of speech alone: happy and unhappy are both adjectives. A suffix normally changes the part of speech: happy is an adjective, happiness is a noun, happily is an adverb.

This is why exam questions are solved from the sentence rather than from the word. The blank sits in a grammatical position that requires one particular part of speech, and your job is to produce the form of the given root that fills it.

• ✓ His ___ (honest) impressed everyone. → honesty — the blank follows a possessive, so a noun is needed
• ✓ He behaved very ___ (honest). → honestly — the blank modifies a verb, so an adverb is needed

Common prefixes and what they mean

Prefixes grouped by meaning

• ✓ The road is ___ (regular) maintained. → irregularly — prefix ir- plus suffix -ly
• ✓ He ___ (understood) my meaning. → misunderstood

Common suffixes and the word class they make

Suffixes are best learned in four groups, one for each part of speech they produce. If you know which group the sentence needs, you can usually recall the right suffix even for a word you have not met.

• ✓ His ___ (kind) touched us all. → kindness — a noun of quality
• ✓ The play was ___ (success). → successful — the blank follows was, so an adjective is needed

How to read the blank

Because the answer depends on grammatical position, a short checklist solves almost every question. Look at what stands immediately before and after the blank.

• After a, an, the, his, her, their, or an adjective → a noun is needed.
• After a form of be (is, was, were) or before a noun → an adjective is needed.
• After a full verb, or modifying an adjective → an adverb is needed.
• After to, or after a modal → a verb is needed.
• If the sentence is negative in sense but has no not → a negative prefix is probably wanted.

• ✓ He is a ___ (care) driver. → careful — between an article and a noun, so an adjective
• ✓ She drives ___ (care). → carefully — after a full verb, so an adverb

Spelling changes to watch

Adding an affix sometimes changes the spelling of the root. These changes are regular, and getting them wrong costs the mark even when the affix is right.

• A final -y after a consonant becomes -i: happy → happiness, beauty → beautiful, carry → carrier.
• A final silent -e is dropped before a vowel suffix: care → caring, use → usable, nature → natural.
• A final -e is kept before a consonant suffix: care → careful, hope → hopeless.
• Words ending in -ce or -ge keep the e before -able and -ous: notice → noticeable, courage → courageous.
• in- becomes im- before b, m, p (impossible), il- before l (illegal), and ir- before r (irregular).

• ✗ happyness ✓ happiness — final -y after a consonant becomes -i
• ✗ carefull ✓ careful — the suffix -ful has a single l

Practice

Work through these before you check the answers — the reasoning matters more than the answer.

1. He is a man of great ___ (wise).
2. The work was done ___ (careful).
3. Smoking is ___ (harm) to health.
4. His answer was ___ (correct).
5. We should ___ (strong) our friendship.
6. She is famous for her ___ (kind).
7. The instructions were ___ (understand) by everyone.
8. He is one of the most ___ (success) businessmen.

Answers

1. wisdom — after “great” a noun is needed.
2. carefully — it modifies the verb, so an adverb.
3. harmful — after “is”, an adjective.
4. incorrect — the sentence needs the negative sense, so the prefix in-.
5. strengthen — after “should”, a verb.
6. kindness — after a possessive, a noun.
7. misunderstood — the sense is negative, so the prefix mis-.
8. successful — before a noun, an adjective.