The phrase "their introductory" is correct and usable in written English.
It can be used when referring to something that serves as an introduction related to a specific subject or group.
Example: "In their introductory remarks, the speakers outlined the main objectives of the conference."
Alternatives: "their opening" or "their initial".
What was their introductory conversation?
The Nets held their introductory news conference for Williams the same day Anthony made his debut at Madison Square Garden.
But when their introductory price for cable TV and Internet access expired this year and the bill soared to $150, the couple halved it by cutting TV.
Billups, the established All-Star, sat to the side, literally, while Anthony fielded the bulk of the questions during their introductory news conference last week.
Both Mr. Romney and Mr. Obama hold fund-raisers that are closed to the news media, but they frequently allow reporters to record their introductory speeches.
About two million people have subprime mortgages with monthly payments that are likely to jump sharply in the next year or so as their introductory teaser rates expire.
And the reason lecturer after lecturer, at more than 15 different open days, was incredulous when she zoomed into their introductory talk is because she uses a wheelchair.
After their introductory scenes, when each is allowed a defining crotchet or two, Lester, Pilar and Maybelle are pretty much interchangeable as characters, except when they contribute something to the puzzle-solving from their specific technical backgrounds.
Their states might, as their introductory letter to Congressional leaders pointed out, "represent over one-third of the nation's gross domestic product," but in the Capitol, they feel overlooked.
In their introductory remarks, Mr. White recited W. S. Merwin's translation of Guillaume Apollinaire's "Autumn" in which he sadly observes that "the autumn has been the death of summer".
Film-maker Mike Figgis, who directed Downey as an artist with Aids in 1997's One Night Stand, recalls him arriving for their introductory meeting barefoot, high and brandishing a handgun.
