a group of letters
added to the end of a word
used to change the function of a word
turning a noun into an adjective
an adjective into an adverb
noun > adjective: My gran has good health. My gran is healthy.
There wasn't any danger. It wasn't dangerous.
adjective > adverb: He was very quick. He walked very quickly.
I am happy to help. I will happily help you.