Every language has a large number of words for users to choose when they need to communicate. Words are important parts of linguistic knowledge. Without words we are not able to convey our thought through language.
This unit is about words: their relations, their constituent parts, and their internal organization. The study of the internal structure of words, and of the rules by which words are formed, is morphology.
Morphology
As a lexical word, morphology consists of two parts: morph+ olog. The word morph means "form". The suffix-ology means "branch of knowledge concerning" Therefore, the meaning of morphology is the science of word forms. As linguistics term, morphology is the study of how words are built. Generally, it aims to describe the structure of words and patterns of word formation.
Words
A fundamental unit with which morphology is concerned is the word and its constituents. A word is a symbolic unit which is a combination of meaning and sound. Words may be simple, composite, or compound.
A simple word is composed of only one lexical structure. The word bird, for example, consists of one lexical constituent. It is the minimum free form which can stand by itself and act as a meaningful utterance.
A composite word, also known as complex is composed of two or more substructures The word careful, for example, is a derivation from the lexical substructure care and il.
A compound word is composed of two substructures. For example, the word bookstore is the combination of the lexical substructure book and store.
Simple, composite and compound words are subsumed under the general term morphological expression.