dead certain

Dead Certain: The Presidency of George W. Bush is a 2007 book by Robert Draper. The book tells the story of the George W. Bush Administration from 2001 to 2007.Draper wanted to tell the story of the Bush White House with an inside perspective. To this end, and in preparation for writing the book, Draper had six one-on-one interviews with President Bush. He also personally interviewed Laura Bush, Dick Cheney, Donald Rumsfeld, Condoleezza Rice, Karl Rove, and about 200 other individuals.
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very certain, very sure, positive He's dead certain that Ming is the man who talked to him.