March 2026 · Vocabulary
Understanding how English words are built from prefixes, roots, and suffixes is one of the most powerful vocabulary-building strategies. A student who knows the prefix "un-" means "not" and the suffix "-able" means "can be done" can decode "unbelievable," "unavoidable," "uncomfortable" — and hundreds more words without ever having studied them individually.
| Prefix | Meaning | Examples |
|---|---|---|
| un- | not, opposite | unhappy, undo, unusual, unfair |
| re- | again | rewrite, redo, reconsider, rebuild |
| dis- | not, opposite | disagree, disappear, disconnect, dislike |
| mis- | wrongly | misunderstand, misspell, mislead, misuse |
| over- | too much | overwork, overcook, overreact, oversleep |
| under- | too little | underestimate, underpay, undervalue |
| pre- | before | preview, predict, prepare, preschool |
| inter- | between | international, interact, interview |
| Suffix | Function | Examples |
|---|---|---|
| -tion / -sion | verb → noun | education, decision, information |
| -ment | verb → noun | development, agreement, achievement |
| -ness | adjective → noun | happiness, kindness, darkness |
| -er / -or | person who does | teacher, actor, writer, driver |
| -ity | adjective → noun | creativity, ability, possibility |
| Suffix | Function | Examples |
|---|---|---|
| -able / -ible | can be done | comfortable, responsible, visible |
| -ful | full of | beautiful, helpful, wonderful |
| -less | without | careless, homeless, useless |
| -ous | having quality | dangerous, famous, nervous |
| -ive | having quality | creative, active, expensive |
| Suffix | Function | Examples |
|---|---|---|
| -ize / -ise | to make | organize, realize, modernize |
| -en | to make | widen, strengthen, darken |
| -ly | adjective → adverb | quickly, carefully, happily |
The classic Cambridge exam format. Provide a base word and a sentence — students transform the word to fit: "The movie was really _____. (ENJOY)" → "The movie was really enjoyable."
Students complete tables with all forms of a word: noun, verb, adjective, adverb. E.g., create | creation | creative | creatively. Great for systematic review.
Give adjectives — students add negative prefixes: happy → unhappy, possible → impossible, regular → irregular, legal → illegal. Focus on which prefix goes with which word.
Give students a root and challenge them to find all English words containing it: "port" (carry) → transport, export, import, portable, report, support, airport.
Provide a list of words. Students sort them by suffix and determine the word class (noun, adjective, verb, adverb). This reinforces the relationship between form and function.
| Error | Correct Form | Rule |
|---|---|---|
| *informations | information | Some -tion nouns are uncountable |
| *unpossible | impossible | -possible takes im-, not un- |
| *happyness | happiness | y → i before -ness |
| *beautifull | beautiful | -ful has one l, not two |
| *strongness | strength | Irregular noun form |
Introduce basic prefixes (un-, re-) and common suffixes (-er, -tion) at A2. Systematic word formation work is most effective at B1–B2, where students have enough base vocabulary to see patterns. For Cambridge exam preparation (FCE/CAE), intensive word formation practice is essential.
Group words by prefix pattern: un- is the most common negative prefix. Im-/in-/ir-/il- follow spelling patterns (im- before b/m/p, ir- before r, il- before l). Create reference charts and practice with gap-fill exercises using AI-generated worksheets.
Yes! Use the Fill in the Blanks generator with a grammar focus on word formation, or the Sentence Transformation exercise type. You can also use Negative Prefixes exercises specifically designed for prefix practice.
Part of the Edooqoo ESL exercise design hub.
Edooqoo — Word Formation Exercises: 60 Prefix & Suffix Prompts. Prefix, suffix and part-of-speech drills for B1-C1 adults, with 60 prompts and a marking key. Generate a word-formation worksheet for your student. Materials are CEFR-aligned across A1 to C2 and target a single named lesson goal.