-ful:
* Boastful: (adjective) characterized by boasting; arrogant.
* Example: "He was a boastful man who always talked about his accomplishments."
-er:
* Boaster: (noun) a person who boasts.
* Example: "The boaster in the corner was annoying everyone with his stories."
-ing:
* Boasting: (verb - present participle) the act of boasting.
* Example: "He was caught boasting about his latest investment."
-ingly:
* Boastingly: (adverb) in a boastful manner.
* Example: "He boastingly declared himself the best player on the team."
-ed:
* Boasted: (verb - past tense) to have boasted.
* Example: "She boasted about her new car."
-able:
* Boastable: (adjective) capable of being boasted about.
* Example: "His accomplishments were highly boastable."
-fully:
* Boastfully: (adverb) in a boastful manner.
* Example: "He spoke boastfully about his wealth."
Less Common Suffixes:
* -less: (While "boast" doesn't naturally lend itself to "less" suffixes, you could use it in a figurative sense.)
* Boastless: (adjective) lacking boastfulness; modest.
* Example: "He was a boastless man who preferred to let his actions speak for themselves."
It's important to note that some of these suffixes might not be as common as others, and their meaning might be more nuanced.