Affixation is a process which involves adding bound morphemes to roots which results in a newly-created derivative. Whereas we can distinguish many types of this process, the English language generally makes use of two — prefixation and suffixation. The first is characterised by adding a morpheme that is placed before the base: mature — premature, do — undo, affirm — reaffirm, function — malfunction. In contrast, suffixation focuses on attaching a morpheme that rather follows the base than proceeds it: read — reader, friend — friendship, manage — management. What is also characteristic for this type of affixation is the fact that suffixes can be stacked on one another — this does not happen when it comes to prefixes: re-spect-ful-ness, friend-liness, un-help-ful-ness. It should be noted that affixes are divided into two main categories: while some of them are labelled as inflectional, a majority of them is known to be derivational.
Derivational affixes can change the word-class of the derivative and can be either prefixes or suffixes — therefore they can produce new lexemes. However, the meaning they carry is not always fixed — eg. X-ise carries the meaning of either "put into X (computerise — 'put into a computer'), make more X (modernise — 'make more modern' or provide with X (brotherise — 'provide with a brother').
Another type of affixes is labelled as inflectional. They differ from the other type in the way that once attached, they will never change the word-class of a derivative. Also, their grammatical function is very much fixed: the plural -s suffix always creates plural forms of nouns: dog — dogs, cat — cats. In fact, they do not produce new words in English, but rather provide the existing lexemes with new forms:
- the plural [-s] - creates plural forms of nouns: dog — dogs, cat — cats, bush — bushes,
- Saxon genitive ['s] - indicates possession: Robert — Robert's (clothes), children — children's (toys), Jesus — Jesus' (mercy),
- the past tense [-ed] - creates past forms of regular verbs: walk - walked, delve -delved,
- the third person singular [-s] - enforced by the English grammar in the Present Simple tense: She works there, The knife proves sharp,
- the progressive [-ing] - used in progressive forms of verbs: go — going, see — seeing, ski — skiing,
- the comparative [-er] - forms comparative adjectives: wide — wider, high — higher, far — farther,
- the superlative [est] - forms superlative adjectives: wise — widest, high — highest, far — furthest.
Another type of affixation that can be encountered in either English or Polish (though to a rather limited scope) is infixation, which involves putting a morpheme in the middle of a word structure rather than taking lateral positions: al-bloody-mighty, kanga-bloody-roo. In the English language this only serves as a tool of emotionally colouring swear-words to give them greater an impact.
Yet another type of suffix are interfixes. They are used in Polish compounds and blends to ensure phonological feasibility of a word: śrub-o-kręt, park-o-metr, lod-o-łamacz and are meaningless phonemes that connect two bases. They do exist in English but due to the fact that English compound-formation does not require such measures their number is scarce (eg. speedo-meter).