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Prefixes & suffixes



Prefixes are added to the beginning of a word to make a new word, e.g. mis+take. Some common prefixes are 'mis', 'dis', 're', 'for', 'anti', 'ante', 'sub', 'un' and 'in'. New words are made by placing a prefix in front of a word. It is helpful to know the meanings of prefixes.

Prefix 're' means again, therefore reappear means to appear again.

Common prefix meanings

pre - before

mis - bad(ly)

sub - under

inter - between

semi - half

The following prefixes of 'im', 'ir', 'il', 'in' and 'un' can be added to the beginning of words to make them into a negative.


im + possible = impossible

ir + responsible = irresponsible

il + legal = illegal

in + active = inactive

un + happy = unhappy


Letters added to the end of a main word are called suffixes. Common suffixes are: 'ed', 'ful', 'ly', 'ing', 'able', 'ance', 'ence', 'ness'.


harm + less = harmless

When 'full' is added to a word you drop the final 'l'. If you add 'ly' to any word ending with 'ful' you keep the existing 'l'.


hand + full = handful

rest + full = restful

restful + ly = restfully