Prefixes:
Adding meaning to the beginning of a word:
* anti-: against (antibiotic, antifreeze)
* auto-: self (automatic, autobiography)
* bi-: two (bicycle, bilingual)
* co-: together (cooperate, coexist)
* de-: remove, down (decompose, decrease)
* dis-: not (disagree, disappear)
* en-: make (enlarge, enrich)
* fore-: before (forewarn, forecast)
* in-: not (inactive, impossible)
* mis-: wrongly (misunderstand, misinterpret)
* non-: not (nonfiction, non-profit)
* pre-: before (premature, preview)
* re-: again (redo, rewrite)
* sub-: under (submarine, substandard)
* super-: above (superman, supersize)
* un-: not (unhappy, unlock)
Suffixes:
Adding meaning to the end of a word:
* -able/-ible: able to be (readable, edible)
* -al/-ial: relating to (national, judicial)
* -er/-or: one who (baker, actor)
* -ful: full of (beautiful, helpful)
* -ing: action or process (walking, singing)
* -ism: belief or practice (capitalism, feminism)
* -ity/-ty: state or quality (clarity, honesty)
* -less: without (hopeless, careless)
* -ment: action or result (movement, payment)
* -ness: state or quality (happiness, darkness)
* -ship: state or quality (friendship, citizenship)
* -tion/-sion/-ion: action or process (creation, decision, completion)
* -y: having the quality of (sleepy, dirty)
Note: This is not an exhaustive list, and many other prefixes and suffixes exist.
Example:
* Word: "happy"
* Prefix: "un-" (meaning "not")
* Suffix: "-ness" (meaning "state or quality")
* Resulting word: "unhappiness" (meaning "the state of not being happy")