Nabokov's subsequent protests that he had no knowledge of the C.I.A. connection are difficult to credit.
Britten is probably best known as a composer of opera, and his achievement in this field is difficult to credit.
A narrator who trades in such banalities is difficult to credit, and the writer who lends him those words seems uninterested in persuading us that they mean anything.
One hears so much about Social Security and its problems ("Fabricating a Crisis," by Paul Krugman, column, Aug. 21) that it's difficult to credit anyone.
The story related is simple, and suspiciously self-referential — it's difficult to credit that a first novel would so blithely assume so much familiarity with a cast of characters never before encountered.
The notion that the Cold War national-security state, which Eisenhower warned against, might have decided to kill the President is not as difficult to credit as one wishes.
Many of the stories that come down to us are difficult to credit; for example, before Claudius had his third wife, Messalina, whacked, she was reported to have held a twenty-four-hour sex competition with a hooker.
It's difficult to credit that this genuine epic cost as little as $16.5 million (assembled from United Artists, Pathe, the British Arts Council, Canal Plus in France and the BBC).
