根据以下资料,回答15~18题。
Of all Barry H.Landau's anecdotes about his friendships with presidential dogs, perhaps the best is the one about the time the Clinton White House called to postpone his play-date with Buddy.
Yes, Landau is both human and an adult, a 60-year-old author, presidential historian, former White House protocol officer and memorabilia collector.But so enamored is he of dogs, and so well connected to a succession of presidents, that he had an appointment for a South Lawn romp one day with Buddy, Bill Clinton's Labrador retriever (拉布拉多犬) .
Logistics got in the way, though, and hence Clinton secretary Betty Currie's apologetic voice mail left at the Smithsonian Institution, where Landau was doing research: "I'm sorry, but we'll have to reschedule Mr.Landau's play-date with Buddy."
Not surprisingly, this is a happy week for Landau, with the new Obama family dog, Bo, joining a White House tradition that dates to George Washington.It's one that Landau feels is invaluable to a presidency.
"Having a dog just humanizes a president," he says."It completes the picture.It's something people can relate to."