Writing Mini-Lessons: Root Words and Prefixes

Affixes can cause spellers difficulties. It is easy to become confused about whether letters should be doubled when you add a prefix at the beginning of a word or a suffix to the end. Below are some basic definitions, and the one significant prefix rule.

Some Definitions:

A Rule that Mostly Works: Prefixes

To add a prefix to a root word, just attach it: don’t drop or double any letters.

Examples:

appear + prefix = disappear or reappear

appoint + prefix = disappoint or reappoint

necessary + prefix = unnecessary

apply + prefix = reapply

school + prefix = preschool

daughter + prefix = granddaughter

commend + prefix = recommend

mortal + prefix = immortal

arrange + prefix = rearrange

establishment + prefix = antiestablishment

active + prefix = inactive

moralize + prefix = demoralize

enlist + prefix = reenlist

colon + prefix = semicolon

activate + prefix = deactivate

gust + prefix = disgust

legal + prefix = illegal

literate + prefix = illiterate

regular + prefix = irregular

do + prefix = redo or undo

contract + prefix = subcontract

scribe + prefix = transcribe

able + prefix = unable