Morphology - Unit Three - Lesson No. 17
Affixes are of two types: inflectional and derivational. By adding inflectional affixes to a root, we create different grammatical forms of the same word. For example, speak, speaks, spoke, spoken and speaking. When we add derivational affixes to a root, then we create a new word. For instance, adding a prefix such as –er to speak and write will result in speaker and writer which are different words.
As seen in the example above, inflectional affixes produce different forms of the same lexeme whereas derivational affixes produce new lexemes. In other words, inflectional affixes have a grammatical function whereas derivational affixes have a lexical function.
Inflectional affixes form a part of a closed system. For instance, number and person in English are closed systems in which number has only two variables (singular and plural) and person has only three variables (first person, second person, and third person). Adding one more variable to any of the systems will mean radically changing the entire system. Derivational affixes, on the other hand, are constantly added to the present stock of affixes in English, for example, particularly in the field of science and technology, but it does not in any way cause a radical change in the nature of any one of the systems already in use. The suffix –nik taken from the Russian word sputnik has resulted in the formation of a large numer of words in English, for example, beatnik, computernik and Freudnik .
Inflectional affixes mark agreement but derivational affixes do not do that. The following sentences show how the suffix at the end of a verb in Arabic marks the agreement of the verb with the gender of the subject:
It has to be noted that derivational affixes never operate as markers of this kind of grammatical agreement.
In words in which both inflectional and derivational affixes are present, the derivational affix occurs closer to the root than the inflectional affix. This can be illustrated with the help of English words like players (play + er + s), employees (employ + ee + s), mountaineer’s (mountain + eer + ‘s) and classifying (class + fy + ing). In all these words, the derivational suffix occurs closer to the root and the inflectional suffix occurs at the end.