A prefix in an affix which placed before the root.of a word mathews 2005 example the work unhappy consists of the prefix un which means not combined with the root work happy the word unhappy mean a not happy (see the prefixes in chapter2,page19)
A suffix is an affix that comes after the from of word whith placed aftwr the root of a word sad combined with the suffix ness thus ness thus is in a suffixal position and the formation of nouns in ness a suffixal formation.