    Sentence 1: It is as if you looked up. say, infer/imply in a  usage manual and. the author's treatment, in place’ of an  explanation and sound advice, weré an unpleasant diatribe  against anyone so dense and rude as to have had to look up  tthe entry to begin with.    Sentence 2: Replacing’ aie explanation with the author's  diatribe would only work ‘in ‘textbooks written by famous  professors.