Morphology; Types of the Morphemes

In morphology, there are two broad categories of morphemes: free morphem and bound morpheme

A. Free Morphemes

What we have described as free morphemes fall into two categories. The first category is that set of ordinary nouns, adjectives and verbs which we think of as the word carrying the ‘content’ of message we convey. This free morpheme is called lexical morphemes and some examples are: boy, men, tiger, sad, long and yellow. We can add new lexical morphemes to the language rather easily, so they are treated as an ‘open’ class of words. 

The other group of free morphemes is called functional morphemes.  The examples are: and, but, when, on, near, in, the, that. This set consists largely of the functional words in the language such as conjunctions, prepositions, articles and pronouns. Because we almost never add new functional morphemes to the language, they are described as a ‘close’ class of words.

 B. Bound Morphemes

Affixes are often named as the bound morpheme. This group includes prefixes, suffixes, infixes, and circum fixes. Prefixes are added to the beginning of another morpheme, suffixes are added to the end, infixes are inserted into other morphemes, and circum fixes are attached to another morpheme at the beginning and end. 

Following are examples of each of these:

Prefix: re- added to do produces redo
Suffix: -or added to edit produces editor
Infix: -um- added to fikas (strong) produces fumikas (to be strong) in Bontoc
Circum fix: ge- and -t to lieb (love) produces geliebt (loved) in German