-ology names a field of study, -ism a belief or practice, and -ist the person tied to it: psychology, capitalism, psychologist.
Naming fields, beliefs, and people
Not ""Psychism studies how people think." (-ism names a belief, not a field)" — say ""Psychology studies how people think." (-ology names the field)". -ology = the field of study; -ism = a belief system.
Try it: Lani: Which subject covers how societies work? Liam: That is ___. Choose the word for the blank. (sociology / socialism / socialist) Answer: sociology — Sociology ends in -ology, the ending for a field of study.
Word
Pronunciation
Example
psychology
/saɪˈkɑlədʒi/
She switched to psychology because she wanted to understand how memory works.
capitalism
/ˈkæpɪtəlɪzəm/
The essay compares capitalism with earlier economic systems.
psychologist
/saɪˈkɑlədʒɪst/
A psychologist reviewed the survey before we published the results.
Building abstract nouns
-ity (usually Latin-looking adjectives) and -ness (usually everyday English ones) turn adjectives into nouns; -ship names a status or role.
Not ""The complexness of the problem surprised us." (wrong suffix for this adjective)" — say ""The complexity of the problem surprised us." (complex takes -ity)". Latin-looking adjectives like complex take -ity, not -ness.
Try it: Which is the standard abstract noun from the adjective 'stable'? (stability / stableness / stableship) Answer: stability — Stable looks Latin, so its noun takes -ity: stability.
Try it: Which word names the status of being a member? (membership / memberity / memberology) Answer: membership — The ending -ship names a status or role, so membership means being a member.
Word
Pronunciation
Example
flexibility
Online modules give us flexibility in how we plan the course.
complexity
The complexity of the plot lost half the audience.
leadership
Strong leadership kept the team calm under pressure.
stability
/stəˈbɪləti/
The new contracts brought some stability to the department.
More endings: actions, abilities, adjectives
-tion and -ment make nouns from verbs, -able or -ible means able to be done, -ish, -al and -ous make adjectives, -ence names a quality.
Try it: Liam: Is this jar okay for the blue bin? Lani: Yes, glass is ___. Choose the word for the blank. (recyclable / recyclement / recyclous) Answer: recyclable — The ending -able means able to be done, so recyclable means able to be recycled.
Word
Pronunciation
Example
contribution
Every small contribution to the fund helps.
development
The development of the app took six months.
washable
These cushion covers are washable at low heat.
childish
Throwing food is childish.
persistence
Her persistence paid off in the end.
What are the common mistakes?
Incorrect
Correct
Why
"Psychism studies how people think." (-ism names a belief, not a field)
"Psychology studies how people think." (-ology names the field)
-ology = the field of study; -ism = a belief system.
"The complexness of the problem surprised us." (wrong suffix for this adjective)
"The complexity of the problem surprised us." (complex takes -ity)
Latin-looking adjectives like complex take -ity, not -ness.