-able, -ible 

able to (adjective)

ineligible, disable, usable

-er, -or

one who dose (noun)

error, user, competitor

-fy 

To make (verb)

beautify, magnify, dignify 

-ism

the practice of (noun)

prism, rationalism, Catholicism 

-ist 

one who is occupied with (noun)

list, insist, segregationist

-less

Without, lacking (adjective)

selfless, timeless, meaningless

-logue, -log

A particular kind of speaking or writing (noun)

prologue, dialogue

-ness

The quality of (noun)

neatness, messiness, meaninglessness 

-ship

The art or skill of (noun)

hardship, sportsmanship, 

-tude 

thestate of (noun)

aditude, rectitude,