book(hell, robert, drama, 500).
book(haha, graham, comedy, 200).
book(murder, fernando, crime, 1000).
book(prog, david, study, 600).
book(made_up, larry, fiction, 300).
book(ref, bob, reference, 700).

holidays(A, B, C, D) :-book(A, B, C, D), (A = _),(B = _), (D < 400), (C\= study; C\= reference).
revision(C, D) :- (D > 300), (C = study; C = reference).
literary(C) :- (C = drama).
leisure(C) :- (C = comedy; C = fiction).