A suffix is a morpheme (a meaningful unit of language) added to the end of a word (the base or stem) to change its grammatical function or meaning.
Here are some examples:
* -ing: (verb) to indicate continuous action (e.g., walk -> walking)
* -er: (noun) to indicate a person or thing that does something (e.g., teach -> teacher)
* -ly: (adverb) to modify an adjective or another adverb (e.g., happy -> happily)
* -ness: (noun) to indicate a state or quality (e.g., kind -> kindness)
* -able: (adjective) to indicate possibility or capability (e.g., break -> breakable)
Let me know if you'd like more examples or information on suffixes!