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KitWren
b2B2 Upper-Intermediate EnglishVocabulary in depthVocabularyabout 18 min

Word formation

Build new words with prefixes and suffixes: un-, dis-, mis-, over-, -ness, -ment, -ity, -able, -ise — essential for exams and vocabulary growth.

In this lesson you will

  • Form nouns, adjectives, verbs and adverbs with suffixes
  • Change meaning with prefixes
  • Choose the right negative prefix

Learn

Noun suffixes: -ment (develop → development), -ness (kind → kindness), -ity (able → ability, popular → popularity), -tion/-sion (decide → decision), -ance/-ence (perform → performance), -er/-or/-ist (teach → teacher).

Adjective suffixes: -ful/-less (care → careful/careless), -able/-ible (rely → reliable), -ous (danger → dangerous), -ive (create → creative), -al (nation → national). Verbs: -ise/-ize (modern → modernise), -en (wide → widen), -ify (simple → simplify).

Negative prefixes: un- (unhappy), in- (incorrect), im- before m/p (impossible), il- before l (illegal), ir- before r (irregular), dis- (disagree).

Meaning prefixes: mis- (wrongly: misunderstand), re- (again: rewrite), over-/under- (too much/little: overcook, underestimate), pre-/post- (before/after), co- (together: co-worker), anti- (against).

Examples

  • Her reliability makes her a great employee.
  • It’s illegal to park here.
  • We underestimated the cost.
  • The city plans to widen the road.

Vocabulary

prefix

letters added to the start of a word

suffix

letters added to the end of a word

underestimate

think something is smaller than it is

reliable

can be trusted

word family

words from the same root

Practice

1 / 8

Complete the sentence.

The of the new park took two years. (DEVELOP)

Speaking

Pick five root words (e.g. use, able, act, nation, care) and say as many related words as you can, using each in a sentence.

Recording isn’t available in this browser. You can still practise: say your answer aloud, then type what you said.

Writing

Write a paragraph (100–130 words) about the pros and cons of technology, using at least ten words formed with prefixes or suffixes. Underline them.

0 / 100+ words

Lesson quiz

1 / 5

Complete the sentence.

Thank you for your . (KIND)

Review

Key points

  • Nouns: -ment, -ness, -ity, -tion, -ance.
  • Adjectives: -ful/-less, -able, -ous, -ive.
  • Verbs: -ise, -en, -ify.
  • Negatives: un-, in-, im-, il-, ir-, dis-; meaning prefixes: mis-, re-, over-.

What you learned

  • ✓ I can build word families.
  • ✓ I choose the right negative prefix.
  • ✓ I can handle word-formation tasks.