Morphemes and their types

Grammatical morphemes

Languages express concepts via two types of meaningful sound: grammatical morphemes and lexemes. Lexemes are simply noun, verb, and adjective stems which express general concepts. Grammatical morphemes are sometimes referred to as 'function words'. 'Grammatical morpheme' is a better term for the functions of language are expressed not only by words but by suffixes, prefixes, and unaccented particles, too. They belong to closed classes to which speakers may not add nor subtract and never refer to general cognitive categories. Grammatical morphemes are those bits of linguistic sound which mark the grammatical categories of language (Tense, Number, Gender, Aspect), each of which has one or more functions (Past, Present, Future are functions of Tense; Singular and Plural are functions of Number). So suffixes like -s and -ed as well as particles like the (Definite) and not (Negative) are grammatical morphemes because they express grammatical functions, not general concepts.

Stylistic Morphology 

Stylistic Morphology deals with the expressive means and stylistic devices on morphological level. The main language unit of morphological level is a morpheme. There are a lot of definitions of a morpheme, but the most wide-spread and accepted in present-day linguistics is the following definition: a morpheme – is the smallest meaningful language unit that can be found in a word. According to the role they play in word construction, morphemesare subdivided into root morphemes and affixes. Morphology as a part of linguistics deals first of all with forms, functions and meanings of affixes. Affixes are divided into two main types: 1) word-building or derivational morphemes: to work – worker, to read – readable, name – namely, workman – workmanship; 2) formative morphemes: boy – boys, lived – lived – is living – has lived. Stylistic morphology deals only with the functions of the formative morphemes because word-building morpheme is a special aspect of linguistics. Formative morphemes are divided in its turn into: 1) synthetic morphemes: boys, lived, comes, going; 2) analytical morphemes: has invited, is invited, does not invite; 3) morphemes using root vowel gradation: write – wrote, meet – met; 4) suppletive morphemes: go – went.
Formative morphemes don’t function independently, they function in the structure of a word. They form different word-forms which indicate different meanings of grammatical categories – number, case, definiteness / indefiniteness, person, voice, tense, aspect, mood, etc.
An expressive means exists in the language due to the fact that the given language unit has both denotative and connotative meanings in its semantic structure, and as it has connotative meaning it is a marked member of a stylistic opposition. An EM can be realized only due to the paradigmatic relations. And we should stress that the main, the basic difference between a word and a word-form is the following: 1) a word possesses denotative meaning and can possess or acquire in a context connotative meaning; 2) any grammatical form has only denotative meaning if taken out of any context. Taken out of a context a grammatical form cannot be defined as stylistically marked, it has no connotative (or additional) meaning.
CONCLUSION
Morphology is the term which had no association with language when it was first coined by the German philosopher and poet Johann Wolfgang von Goethe in the nineteenth century. It was first coined in a biological context. However, the word ‘morphology’ came from the Greek word ‘morph’ which means ‘shape/form’. So, we can say that morphology is the philosophy (‘logos’) of shape or forms. Still, we have not found any clue that morphology is a term related to language or linguistics. In biology and in geology morphology means the structures or forms of the body and the earth respectively. So, in linguistics also, morphology must refer to a study which is related to the forms of language. The most basic form of language is the word. Thus, we can say that morphology is the study of forms of words. To be more specific, morphology is the branch of linguistics that studies the formation of words and their internal structures.
Linguists often define morphology as the study of morphemes.What is a morpheme? A morpheme is the smallest grammatical unit of a language. The linguists who investigate words, the formation of words, and the structures of words are called morphologists. They mostly identify and study morphemes which construct new words.
You cannot divide a morpheme into smaller meaningful parts. You can divide a word according to its syllables. For instance, you can divide ‘wonderful’ into three syllables ‘won’, ‘der’, and ‘ful’ because syllables are determined by sound. However, morphemes are not determined by sound; morphemes are determined through meaning. Every morpheme must contribute a certain meaning to the word. So, the word ‘wonderful’ can be divided into two morphemes ‘wonder’ and ‘ful’. Together these two morphemes form a new word with new grammatical function. But none of these morphemes cannot be divided into more parts which contain meanings.