Natural Language Processing and Computational Linguistics

3Morphology Sphere

3.1. Elements of morphology

Morphology is a branch of linguistics that focuses on the way in which words are formed from morphemes. Morphemes are the smallest linguistic unit which hold any meaning; thus, a word can be composed of one or more morphemes. For example, book, cat and house are simple words, while books, finished and dismiss are complex words because they are made up of multiple morphemes. There are two types of morphemes: lexical morphemes and grammatical morphemes. Also called monemes, lexical morphemes designate common objects such as book, computer, city or flight. These morphemes are distinguished by their number in a given language; it is always possible to add to the list of lexical morphemes with new morphemes, which are generally referred to as neologisms. Grammatical morphemes, on the other hand, concern words that play a grammatical role in a sentence, such as prepositions, articles and pronouns. Because these groups of words cannot in practice be modified by speakers of a language, they constitute closed groups. Thus, it is possible to add a new noun to designate a new object, but not to add a new preposition or pronoun.

The consideration of morphology as an independent branch of linguistics like phonology, syntax and semantics is not unanimous within the linguistic community. Certain syntactic theories, such as distributed morphology, posit that the role of syntax is to make all of the combinations required to construct a sentence, ...