事實真相,本質
nitty-gritty n : the choicest or most essential or most vital part of some idea or experience; "the gist of the prosecutor's argument"; "the heart and soul of the Republican Party"; "the nub of the story" [syn: {kernel}, {substance}, {core}, {center}, {essence}, {gist}, {heart}, {heart and soul}, {inwardness}, {marrow}, {meat}, {nub}, {pith}, {sum}]