Suffixes
B1 · IntermediateWord FormationAct (verb) → action (noun) → active (adjective) → actively (adverb) — one root, four suffixes, four word classes.
What you'll learn
- A suffix attaches to the end of a word and often changes its word class: act (verb) → action (noun) → active (adjective) → actively (adverb)
- Noun-forming suffixes: -tion/-sion, -ment, -ness, -ity, -er/-or (inform → information, govern → government, happy → happiness, active → activity, teach → teacher)
- Adjective-forming suffixes: -ful, -less, -able/-ible, -ive, -al (hope → hopeful, care → careless, wash → washable, create → creative, nature → natural)
- Verb-forming suffixes: -ize/-ise, -ify, -en (modern → modernize, simple → simplify, wide → widen)
- The adverb-forming suffix -ly attaches to an adjective to make an adverb: quick → quickly
What a suffix does
A suffix is a small piece added to the end of a word. Unlike most prefixes, suffixes frequently change a word's part of speech — recognizing a suffix is often the fastest way to tell what class a word belongs to.
Suffixes that form nouns
-tion/-sion, -ment, -ness, -ity, and -er/-or all turn a verb or adjective into a noun, though which one attaches to a given word has to be learned.
Suffixes that form adjectives
-ful, -less, -able/-ible, -ive, and -al turn a noun or verb into an adjective. -ful and -less are often opposites of each other on the same root.
Suffixes that form verbs and adverbs
-ize/-ise, -ify, and -en turn an adjective or noun into a verb. -ly, added to an adjective, is the main way English forms adverbs.
Real English
Watch out
The final -y of 'beauty' changes to -i before -ful is added — a common spelling adjustment when adding suffixes.
'grow' is a verb; the noun form needs the suffix -th (growth), not the bare verb used as if it were already a noun.
Real life — Talking about a job application
"How did your interview go? Did they ask about your qualifications?"
"Pretty well, actually — I felt really confident and gave clear, thoughtful answers."
"That's great! Confidence definitely makes a strong impression."
"I hope so. I should hear back with their decision by Friday."
Practice
Exercise 1 · Choose the correct suffix
Which suffix turns 'act' (verb) into a noun?
Exercise 2 · Choose the correct suffix
Which suffix turns 'care' (noun) into an adjective?
Exercise 3 · Choose the correct suffix
Which suffix turns 'modern' (adjective) into a verb?
Exercise 4 · Choose the correct suffix
Which suffix turns 'quick' (adjective) into an adverb?
Exercise 5 · Choose the correct suffix
Which suffix turns 'govern' (verb) into a noun?
Exercise 6 · Choose the correct suffix
Which suffix means 'able to be done'? (as in 'wash' → 'washable')
Exercise 7 · Choose the correct suffix
Which suffix turns 'happy' into a noun meaning the state of being happy?
Exercise 8 · Choose the correct suffix
Choose the correct word class match: 'active' (adjective) + which suffix = adverb?
Exercise 9 · Complete the word
Add the noun-forming suffix: inform + ___ion → information. (spell only the suffix, without -ion)
Exercise 10 · Complete the word
Add the adjective-forming suffix: hope + ___ → hopeful. (fill in the suffix)
Exercise 11 · Sort the words into groups
0 / 8 sorted
Quick challenge
Five quick questions to check what stuck.
Question 1 / 5
Score: 0/0
Which suffix turns 'friend' (noun) into an adjective?
You learned
- A suffix attaches to the end of a word and often changes its word class.
- Noun-forming suffixes: -tion/-sion, -ment, -ness, -ity, -er/-or.
- Adjective-forming suffixes: -ful, -less, -able/-ible, -ive, -al.
- Verb-forming suffixes: -ize/-ise, -ify, -en; the adverb-forming suffix is -ly.
Related grammar lessons
Compound Words
Learn how English combines two or more words into a single unit with a new, more specific meaning — written as one word, two words, or hyphenated, with no reliable spelling rule to predict which.
Prefixes
Learn how prefixes attach to the front of a word to change its meaning — including the four different negative prefixes English uses (un-, dis-, non-, in-/im-/il-/ir-) and other common meaning-changing prefixes like re-, over-, under-, pre-, and mis-.
Changing Word Classes
An overview of how English words shift between word classes — mainly through suffixes, while prefixes usually change meaning without changing class — and a preview of the more surprising mechanism covered in its own lesson: conversion, where a word changes class with no visible change at all.
Conversion / Zero Derivation
Learn about conversion (zero derivation) — English's most surprising way of changing a word's class, where a word shifts to a new part of speech with absolutely no prefix, suffix, or any change in form at all.