stop up vs introduce

stop up and introduce both are verbs.

Word	Noun	Adjective	Verb	Adverb
stop up	No	No	Yes	No
introduce	No	No	Yes	No

stop up (verb)	introduce (verb)
fill or close tightly with or as if with a plug	be a precursor of
	place, fit, or thrust (something) into another thing
	put before (a body)
	cause to come to know personally
	furnish with a preface or introduction
	bring before the public for the first time, as of an actor, song, etc.
	put or introduce into something
	bring something new to an environment
	bring in or establish in a new place or environment
	bring in a new person or object into a familiar environment