Affixes that come before root words are called prefixes. There are five reasons why prefixes are particularly worth teaching and are well suited for instruction:
- There is a relatively small number of prefixes.
- Prefixes are used in a large number of words.
- Prefixes tend to be consistently spelled.
- Prefixes are easy to identify because they occur at the beginning of words.
- Prefixes usually have a clear lexical meaning.
Researchers found that twenty prefixes account for about ninety seven percent of the prefixed words in printed school English. Four prefixes account for about fifty eight percent of the prefixed words. They are un, re, in, and dis (White, Sowell and Yanagihara, 1989).
Affixes that follow a root word are called suffixes. There are two kinds of suffixes - inflectional and derivational. Inflectional suffixes change the form of the word but not its speech part, these include verb forms, plurals and comparative and superlatives. Derivational suffixes are like prefixes in that they alter a root word’s meaning (Diamond and Gutlohn, 2006).
Morphemic analysis, though useful, does not always work. Some pitfalls include:
- Some prefixes are not consistent with their meaning.
- Sometimes the removal of what appears to be a prefix leaves no meaningful root word.
- Sometimes the removal of what appears to be a prefix of a suffix leaves a word that is not obviously related in meaning to the whole word (White, Sowell and Yanagihara, 1989).