Other Grammar Rules

Prefixes and Suffixes

Prefixes and suffixes are sets of letters that are added to the beginning or end of another word. They are not words in their own right and cannot stand on their own in a sentence: if they are printed on their own they have a hyphen before or after them.


prefix is a group of letters placed before the root of a word. For example, the word “unhappy” consists of the prefix “un-” [which means “not”] combined with the root (or stem) word “happy”; the word “unhappy” means “not happy.”

A short list of prefixes:

Prefix Meaning Examples
de- from, down, away, reverse, opposite decode, decrease
dis- not, opposite, reverse, away disagree, disappear
ex- out of, away from, lacking, former exhale, explosion
il- not illegal, illogical
im- not, without impossible, improper
in- not, without inaction, invisible
mis- bad, wrong mislead, misplace
non- not nonfiction, nonsense
pre- before prefix, prehistory
pro- for, forward, before proactive, profess, program
re- again, back react, reappear
un- against, not, opposite undo, unequal, unusual


suffix is a group of letters placed after the root of a word. For example, the word flavorless consists of the root word “flavor” combined with the suffix “-less” [which means “without”]; the word “flavorless” means “having no flavor.”

A short list of suffixes:

Suffix Meaning Examples
-able able to, having the quality of comfortable, portable
-al relating to annual comical
-er comparative bigger, stronger
-est superlative strongest, tiniest
-ful full of beautiful, grateful
-ible forming an adjective reversible, terrible
-ily forming an adverb eerily, happily, lazily
-ing denoting an action, a material, or a gerund acting, showing
-less without, not affected by friendless, tireless
-ly forming an adjective clearly, hourly
-ness denoting a state or condition kindness, wilderness
-y full of, denoting a condition, or a diminutive glory, messy, victory
Gerund or infinitive (Prev Lesson)
(Next Lesson) Infinitive
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