📖 Quick Grammar Reference: Word Formation
| Affix | Function | Example |
|---|---|---|
| un- | negative prefix | happy → unhappy |
| ir- | negative prefix (before r) | regular → irregular |
| -tion | verb → noun | decide → decision |
| -ness | adjective → noun | happy → happiness |
| -ful / -less | noun → adjective (opposite pair) | careful / careless |
| -ly | adjective → adverb | successful → successfully |
Exercise 1 — Fill in the Blank (Change the word in brackets into the correct form to complete each sentence.)
- The film was extremely (SUCCESS).
- She made a (DECIDE) to move abroad.
- His behaviour was completely (RESPONSIBLE).
- Recycling helps to reduce (POLLUTE).
- The new policy will bring significant (DEVELOP) to the region.
- Her (CREATE) ideas impressed the whole team.
- He explained the results very (CLEAR).
- It is (POSSIBLE) to finish the project by Friday.
- The instructions were (LEGAL) in three countries.
- Their friendship grew stronger through years of mutual (SUPPORT).
Exercise 2 — True or False (Read each statement about word formation and circle T (True) or F (False).)
-
Adding a prefix to a word usually changes its word class (part of speech).
T F
-
The negative prefix before words starting with l, such as legal, is il-.
T F
-
Adding a suffix to a word usually changes its word class.
T F
-
The adjective suffix meaning “full of” is spelled -full, with two ls, as in hopefull.
T F
-
A word family is a group of related words built from the same root, such as decide, decision, decisive, decisively.
T F
Print version: write T or F on the line next to each statement.
Exercise 3 — Build the Word Family (Write the missing noun, verb, adjective, or adverb form to complete each family.)
- Noun: creation | Verb: create | Adjective: ______ | Adverb: creatively
- Noun: success | Verb: succeed | Adjective: successful | Adverb: ______
- Noun: ______ | Verb: analyse | Adjective: analytical | Adverb: analytically
- Noun: strength | Verb: strengthen | Adjective: ______ | Adverb: strongly
- Write your own sentence using one word from each of the four families above.
📋 Show Answer Key
Exercise 1
- successful
- decision
- irresponsible
- pollution
- development
- creative
- clearly
- possible
- illegal
- support
Exercise 2
- False — Prefixes usually change meaning, not word class (happy → unhappy, still an adjective)
- True — il- is used before roots starting with l: legal → illegal
- True — Suffixes usually change the word class (happy → happiness)
- False — The correct spelling has one l: -ful, as in hopeful
- True — This is the correct definition of a word family
Exercise 3
- creative
- successfully
- analysis
- strong
- Open answer. Check that students correctly combine one noun, verb, adjective, or adverb from the families above into a grammatically correct sentence.
Word Formation Worksheet — FAQ
What does this word formation worksheet cover?
This worksheet covers negative prefixes (un-, in-, im-, il-, ir-, dis-), noun and adjective suffixes (-tion, -ness, -ful, -less), and building full word families (noun, verb, adjective, adverb) from a single root.
What level is this word formation worksheet?
This worksheet is designed for B1 (Intermediate) to B2 (Upper-Intermediate) learners, including those preparing for IELTS, Cambridge B2 First, or C1 Advanced exams.
What is the difference between a prefix and a suffix?
A prefix is added to the front of a word and usually changes its meaning but not its word class, e.g. happy → unhappy (still an adjective). A suffix is added to the end of a word and usually changes the word class, e.g. happy → happiness (noun).
How do I choose between un-, in-, im-, il-, and ir- for negative meaning?
un- is most common with native English words (unhappy, unusual). in- is used mainly with Latin-origin words (incorrect) and changes to im- before m/p/b (impossible), il- before l (illegal), and ir- before r (irregular).
Can I save this worksheet as a PDF?
Yes. Click the orange ‘Print / Save as PDF’ button at the top of the page. In your browser’s print dialogue, select ‘Save as PDF’ as the destination. The worksheet is formatted for A4 paper.
Is the answer key included?
Yes. Scroll to the bottom of the worksheet to find the collapsible answer key. Click ‘Show Answer Key’ to reveal all answers. If you want to print the answers too, open the key before clicking Print.
What online exercise goes with this worksheet?
The related online exercise is the Grammar Quiz at lexfizz.com/exercises/quiz/ — it tests your ability to identify the correct prefix, suffix, or word class with instant feedback.
What is a word family?
A word family is a group of words that share the same root, such as decide (verb), decision (noun), decisive (adjective), and decisively (adverb). Knowing full word families is directly tested in exams like IELTS and Cambridge B2 First.
How is word formation tested in exams?
In Cambridge Use of English Part 3, you are given a root word in capitals and must change its form to fit the gap. In IELTS, a wide vocabulary range using correct prefixes and suffixes is assessed under Lexical Resource in the Writing test.
How long does this worksheet take to complete?
The three exercises take approximately 20–25 minutes for most B1–B2 learners. Allow extra time for the writing task in Exercise 3 if students need to think carefully about forming original sentences.