English Word Formation Guide
Prefixes & Suffixes
Understanding prefixes and suffixes helps you decode unfamiliar words in YDS. When you encounter an unknown word, breaking it into parts reveals its meaning.
Common Prefixes
| Prefix | Meaning | Examples | In a sentence |
|---|---|---|---|
| un- | not / opposite | unhappy, unusual, uncertain | She felt uncertain about the outcome of the experiment. |
| re- | again | rebuild, reconsider, rewrite | The committee decided to reconsider the proposal. |
| dis- | not / opposite | disagree, disappear, disconnect | Experts disagree on the long-term effects of this policy. |
| mis- | wrongly | misunderstand, mislead, misinterpret | The data was easy to misinterpret without context. |
| pre- | before | predict, prevent, prehistoric | Scientists can predict earthquakes with increasing accuracy. |
| over- | too much | overcome, overlook, overwhelm | The sheer volume of information can overwhelm students. |
| under- | too little / below | underestimate, underlying, undertake | Researchers often underestimate the role of social factors. |
| inter- | between | international, interdisciplinary, interact | The project requires an interdisciplinary approach. |
| trans- | across | transform, transmit, transparent | The virus can transmit across different species. |
| anti- | against | antibiotic, antisocial, anticipate | Overuse of antibiotics leads to resistant bacteria. |
| co-/com-/con- | together | cooperate, comprehensive, counteract | Nations must cooperate to address climate change. |
| de- | reverse / remove | decline, decrease, deteriorate | Air quality continues to deteriorate in urban areas. |
| ex- | out / former | extensive, exclude, extract | The study involved extensive field research over two years. |
| in-/im-/ir-/il- | not | inevitable, impossible, irrelevant, illegal | Some degree of change appears to be inevitable. |
| sub- | under | submit, subsequent, subordinate | The subsequent analysis confirmed the initial findings. |
| super- | above | supercharge, superior, supervise | Managers are expected to supervise daily operations. |
Common Suffixes
-tion / -sionnoun
education, decision, manipulation
-mentnoun
displacement, environment, government
-nessnoun
awareness, effectiveness, weakness
-ity / -tynoun
reliability, diversity, novelty
-ous / -iousadjective
autonomous, cautious, previous
-iveadjective
comprehensive, invasive, alternative
-aladjective
crucial, hypothetical, fundamental
-fuladjective
careful, powerful, meaningful
-lessadjective
careless, endless, regardless
-able / -ibleadjective
sustainable, accessible, incredible
-lyadverb
ultimately, extensively, consistently
-izeverb
recognize, prioritize, summarize
-ifyverb
clarify, identify, justify
-enverb
strengthen, broaden, threaten
Word Analysis Practice
Tap a word to break it into its parts and discover the meaning. Try to figure it out before revealing the answer!
Prefix
Root
Suffix