* gentle: This is the base word, meaning "kind, mild, or soft."
* -man: This is a bound morpheme, meaning "human being, especially a male."
* -ly: This is a suffix indicating manner or quality, turning "gentleman" into an adjective meaning "having the qualities of a gentleman."
* -ness: This is a suffix indicating state or quality, turning the adjective "gentlemanly" into a noun meaning "the state or quality of being gentlemanly."
Therefore, the morphemes in "gentlemanliness" are:
* gentle
* -man
* -ly
* -ness