Word formation creates new words from existing ones using prefixes (mis-, over-, under-, re-, out-, il-, ir-), suffixes (-tion, -ity, -ness, -ous, -ify, -ise), and conversion (using a word in a different class without changing its form). Mastering word families is essential for C1 vocabulary range and accuracy.
Prefixes change meaning without changing the word class. Common C1 prefixes: mis- (wrongly), over- (too much), under- (too little), re- (again), dis- (not/reverse), out- (surpass). Choose the correct prefixed form.
| Prefix | Meaning | Examples |
|---|---|---|
| mis- | wrongly / badly | mismanage, misinterpret, mislead, misuse |
| over- | too much / beyond | overestimate, overlook, overreact, overpay |
| under- | too little / below | underestimate, underpay, undermine, understate |
| re- | again | redraft, reconsider, restructure, renegotiate |
| out- | surpass / beyond | outperform, outnumber, outlast, outweigh |
| dis- | not / reverse | disagree, discourage, disregard, discredit |
| un- | not (most common) | unprecedented, unwavering, unresolved, undo |
| in-/im-/il-/ir- | not (before specific letters) | inaccurate, impossible, illegal, irrational |
| non- | not (technical/neutral) | non-standard, non-renewable, non-compliance |
| Suffix | Function | Examples |
|---|---|---|
| -tion / -sion | verb → noun | implement → implementation, conclude → conclusion |
| -ment | verb → noun | develop → development, assess → assessment |
| -ance / -ence | adj/verb → noun | coherent → coherence, prevalent → prevalence |
| -ity / -ty | adj → noun | valid → validity, stable → stability, equal → equality |
| -ness | adj → noun | effective → effectiveness, aware → awareness |
| -ous | noun → adj | ambition → ambitious, caution → cautious |
| -ive | verb → adj | conclude → conclusive, produce → productive |
| -ify | noun/adj → verb | simple → simplify, intense → intensify |
| -ise / -ize | noun/adj → verb | modern → modernise, standard → standardise |