The Structure of English Language - Morphology

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This is the study of the structure of words. The name comes from Greek morphos (=shape or form). The smallest units of meaning may be whole simple words (e.g. man, run, big) or parts of complex words (e.g. un-, -faith- and -ful in unfaithful) which are called morphemes.

Some morphemes, such as faith in un-faith-ful or dream in dream-ing can stand alone as words which make sense. These are known as free morphemes. You will see how very many simple words are free morphemes, but can combine with other morphemes, both free and bound (see below) to form complex words.

Where two simple words are joined together to form a new complete word, this is called a compound word. Examples include teapot, starlight and careworn. When these terms are first coined, they are shown in some dictionaries with a hyphen, as light-house or fish-finger.

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Other morphemes, such as prefixes and suffixes (collectively called affixes), cannot stand alone - they need to be part of a complex word to make sense. Examples are

  • dis- in dis-miss, dis-pute or dis-grace,
  • -ing in dream-ing,
  • -ness in happi-ness or sad-ness and even
  • -s used to form plurals, as in boy-s or horse-s.

These morphemes are said to be bound morphemes.

Inflection and derivation

Bound morphemes are traditionally divided into two further classes. Sometimes a word is changed in its form to show the internal grammar of a sentence (“agreement”). Examples would be plural forms of nouns (dog + s → dog-s) or past (imperfect) tenses of regular verbs (want + ed → want-ed). The study of such changes is inflectional morphology (because the words in question are inflected - altered, in this case by adding a suffix).

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Other compound or complex words are made by adding together elements without reference to the internal grammar of a sentence. For example, the verb infect suggests a new verb disinfect (=to undo the action of infecting). New words are often formed by noun + -ize, noun + ism, or verb + able (scandalize, Thatcherism, disposable). The study of such words, “derived” from existing words or morphemes is derivational morphology. The elements of which the word is made may have a grammatical relationship within the word (you may find this idea difficult), but their formation is independent of the syntax of the clause or sentence in which they occur. If you find this puzzling, two things may help:

  • Inflectional morphology is much easier to recognize. A relatively small number of types of inflection (showing number or tense, say) covers most cases.
  • All compound and most complex words show derivational morphology. If a complex word does not show inflection it will show derivation.

But note: a complex word may show both inflection and derivation! A derived word may be inflected to show, for example, tense or number: deported or disposables (as in nappies).

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This table shows how the most common kinds of inflection are found in three word classes:

Inflection of nouns, verbs and qualifiers

Adjectives and adverbs

Addition of terminal s to show plural (one cat; two cats);

addition of 's to show possession (Henry's cat).

Ending shows tense (wanted) or person ([she] wants).

Addition of -er comparative (hotter; likelier);

addition of -est → superlative (coldest; soonest).

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This table illustrates how derivation can occur:

Derivational morphology in complex words


Base of Word


Complex Word

















Un, co


ive, ly



likely (y becomes i)



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Remember that morphology is the study of the structure of words. The structure of words can also be studied to show how the meaning of a given morpheme, or its relation to the rest of the word, varies from one complex word to another. Consider how sun works in the following words: sunbeam, sunburnt, sundial, sunflower, sunglasses, sunlight, sunrise, sun-spot (scientific sense), sun-spot (tourist sense), suntan.


Inflection does not really yield “new” words, but alters the form of existing ones for specific reasons of grammar. Derivation, on the other hand, does lead to the creation of new words. There are at least four normal processes of word-formation, of which three are examples of derivation:

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Four kinds of word-formation








(not derivational)

Affix placed before base of word, e.g. disobey

Affix placed after base of word, e.g. kindness

Two base forms are added together, e.g. blackbird

Word changes class, without any change of form, e.g. (the) pet (n) becomes (to) pet (vb.)

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Words considered as wholes can be categorized according to how they work within phrases, clauses or sentences. These categories, traditionally called parts of speech are now more usually known as word classes. Parts of speech are labels for categories in which words are usually placed. But in a given sentence a word from one category may behave as if it were in another. A dictionary will only record established or standard usage.

The traditional parts of speech were of eight kinds, excluding the two articles (a/an, the). These were nouns, pronouns, adjectives, verbs, prepositions, conjunctions, adverbs, and interjections. Modern linguists prefer to list words in classes that are coherent - all the words in them should behave in the same way. But if this principle were applied rigidly, we would have hundreds of classes, so irregularities are tolerated!

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