Inflection and derivation are the two basic elements of English morphology. Inflection refers to the patterns of word structures and derivation to created words with a new meaning. English has both regular and irregular morphology. It covers pronouns, nouns, verbs and adjectives in all their forms.
Morphology is the study of a word’s internal structure. The word morphology is not related directly to the word morph, as in to change, but comes from the word morpheme. A morpheme is the most basic, but meaningful, unit in the English language. Morphemes can be either free or bound.
A free morpheme is one that has a meaning if left to itself. For example, ‘cat’ is a free morpheme, as is ‘a’ and ‘berry.’ Bound morphemes are words or units that have no meaning by themselves. For example, ‘cran’ and ‘sume’ are bound morphemes and must be combined with another morpheme to make something meaningful such as ‘cranberry’ and ‘resume.’
Inflection, in English morphology, is used to express different grammatical categories, even classes, using the same base word. With nouns, this means indicating number and possessive. With verbs, this means tenses such as third person singular, past, present-continuous and perfect aspect. Adjective inflection is used to indicate comparative and superlative forms.
Elements of English morphology have changed over time. Nouns, verbs and adjectives have lost their gender inflections, for example. Old English verbs were also divided into strong and weak verbs, which they no longer are. Nouns have also lost their links to sentence function such as dative and accusative forms. These now absent forms put English on a par with European languages such as German.
Derivation in English morphology is similar to Noam Chomsky’s mergers. Chomsky defined merging as when two words are placed next to one another to make a new label or meaning like "steam engine" or "hot chocolate." There are various ways of using English words to make new meanings. Two words can be shunted together in what is called compounding, they can be merged into one to make blendings or have their class changed in conversion.
Simple compounds put two words together to create something new. For example, sky and dive combined created "skydive" or dish and washer together makes "dishwasher." Any combination of nouns, verbs and adjectives can be put together to create new words such as "redneck" and "checkmate."
Blendings, in English morphology, refer to the combination of two words where elements of one or both words are removed. This is a shortening of the word to make something more manageable. Examples of blendings include electronic plus mail to make "email" and web plus log to make "blog."
Conversions change a word from one grammatical class to another. For example, it turns a noun like paper into a verb, "to paper." Nouns, adjectives and verbs are theoretically interchangeable in English. This gives writers creative opportunities that many languages do not have, but that does not mean they will be accepted as standard English.