Rules of word formation

In a Nutshell

The goal of this lesson is to explain how words are formed, with emphasis on nouns and adjectives.

Info 1: Suffixes

Suffixes are added after the base or stem of a word. Their main purpose is to demonstrate the class of the word, whether be a noun, an adjective or a verb.

Suffixes	Examples
-dom and *-ism* are used to form nouns.	kingdom, realism
*-er* and *-or* are used to form nouns to describe people who do things.	prisioner, supervisor
-en and *-ify* are used to form verbs.	shorten, modify
*-able* is used to form adjectives.	bendable, reachable
*-ly* is a common suffix used to form adverbs.	slowly, gladly

Info 2: Adjectives From Nouns

There are certain rules when you add a suffix to a noun to form a adjective. For instance, if the noun ends with an -e, it is removed and -y or -al or -ial is added as a suffix. In other cases, adjectives are formed by adding -ly or -ish or -ic. If so, and if the name ends with a -y, it is removed and the suffix is added. There are also the suffixes -ous, -some, -able and -ful.

Suffix	Noun	Adjective
-y	Rain	Rainy
	Sleep	Sleepy
	Cheer	Cheery
	Wind	Windy
-al	Nature	Natural
-al	Person	Personal
-ial	Finance	Financial
-ial	Office	Official
-ly	Cost	Costly
	Friend	Friendly
	Kind	Kindly
-ish	Child	Childish
	Fool	Foolish
	Style	Stylish
-ic	Athlete	Athletic
-ic	Science	Scientific
-some	Fear	Fearsome
-able	Like	Likeable
-able	Rely	Reliable

Additional Info 1: Rules

In order to form adjectives from nouns with the suffix -ous or -ful, there are certain rules within the use of the same suffix.

Suffix	Rule	Noun	Adjective
-ous	If the noun ends with y, remove it.	Mystery	Misterious
	If the noun ends with e, remove it.	Fame	Famous
	If the word ends with cle, it is replaced by cul.	Miracle	Miraculous
-ful	If the noun ends with -ty, it is replaced by I.	Beauty	Beautiful